Best Convertible Car Seat 2026: 12 Seats Tested and Scored

Best Convertible Car Seat Overall

1. Graco 4Ever DLX

Who is this best for?

The 4Ever DLX suits families who want one seat to cover the whole run from newborn to booster, and who value an installation that goes right first time above any headline specification. It is the right choice in a household where more than one adult fits the seat — two parents, a grandparent, a childminder — because it is forgiving of technique in a way the rigid-base seats are not. It also suits anyone who would rather not think about car seats again for a decade. It is less suited to a family committed to extended rear-facing, for reasons that come down to a single number.

Why we love it

It goes in correctly, in most cars, for most people. That is the least glamorous quality a car seat can have and the one that matters most, because a seat installed loose has already given away the majority of the protection it was sold on — and the gap between a theoretically superior seat fitted badly and a good seat fitted well is not close. Four stages take it from rear-facing harness through forward-facing harness to highback and then backless booster, on a ten-year clock, so a single purchase can plausibly cover a childhood. The no-rethread harness moves with the headrest, which you will appreciate roughly every two months without ever consciously noticing it.

Should you buy it?

Buy it unless extended rear-facing is your priority. It stops rear-facing at 40 lb where the Nuna Rava and Britax Poplar S reach 50, and that gap is roughly a year of your child facing the safer direction — the single most consequential trade in this guide. At 21.8 lb it is also a two-handed job to move, so decide which car it lives in before you fit it rather than after. The booster stages are competent rather than class-leading, and by the time you reach them you may want a dedicated booster anyway.

• One of the easiest installs in the category — it goes in right on the first try more often than anything else here
• Ten-year life, and it carries on as a booster long after the harness is done
• No-rethread harness, so growth adjustments take seconds
• Well padded for long drives without being bulky

• 21.8 lb makes moving it between cars a two-hands job. If you swap cars weekly, buy a second base-free seat rather than shifting this one.
• The booster stages are the weakest part of it — good, not class-leading, and by then you may want a dedicated booster anyway.
• Belt install is fine but unremarkable; if your car has awkward buckle stalks, the Poplar S is easier.

Best Extended Rear-Facing

2. Nuna Rava

Safety notice: Nuna recalled 600,000+ Rava seats (models CS-05 and CS-50) made 16 July 2016 – 25 October 2023: debris can jam the harness adjuster. Seats made after 25 October 2023 are unaffected. Buying new, check the date-of-manufacture label. Buying used, assume it needs Nuna's free remedy kit until you have confirmed otherwise.

Who is this best for?

The Rava is for parents who want their child genuinely comfortable on long journeys and who plan to rear-face well past a third birthday. A seat that rear-faces to 50 lb has to hold a child who is nearly school age, and this is the one that does it without the child complaining — which matters more than it sounds, because discomfort is what drives families to turn a seat around early. It suits people who do a lot of motorway driving, and families who care about what the fabric is treated with. It is a poor fit for anyone shopping on value.

Why we love it

The fabric and the room are the best here by a clear margin — deep, plush, no added flame retardants, and shoulder space a four-year-old still fits into comfortably. Mechanically, though, the belt lock-off is the more important feature. Once your child passes roughly 35 lb you must abandon LATCH and install with the vehicle seatbelt, and the Rava makes that transition painless where seats without a lock-off turn it into a wrestling match. The install is push-style with a tensioner and stays tight. Ten-year life, and a shell that still looks presentable at the end of it.

Should you buy it?

Buy it if comfort and rear-facing longevity are what you are shopping for and the budget is there. Be clear that it ties on total score with a seat costing considerably less, and that what the extra money buys is room and materials rather than additional protection — the Britax Poplar S includes an anti-rebound bar the Rava lacks, for meaningfully less. At 26.4 lb with no useful carry points, plan on it living in one car. And check the date of manufacture carefully: units built between July 2016 and 25 October 2023 fall under Nuna's harness-adjuster recall and need the free remedy kit, which matters most if you are buying used.

• Belt lock-off makes a seatbelt install as tight as a LATCH one, which matters once you pass the LATCH weight limit
• Rear-faces to 50 lb — most children will reach four years old still facing backwards
• The nicest fabrics in the group, with no added flame retardants, and genuinely roomy
• Ten-year life

• It ties on total score with a mid-price seat. You are paying for the fabric and the room, not for extra protection.
• 26.4 lb and no carry handles worth the name — plan on it living in one car.
• No anti-rebound bar, which the Poplar S has for less.

Best Install

3. Britax Poplar S

Safety notice: Britax recalled 144,000+ seats in 2026 over a carrying-handle screw — B-Safe Gen2, Flexfit, B-Safe 35, B-Safe Ultra and Endeavors. The Poplar S is not on that list. Check your model on Britax's recall page anyway.

Who is this best for?

This is the seat for anyone who wants the installation to be the easy part. If several different people will be fitting it, or if you will be moving it between cars more than occasionally, the Poplar S survives all of that better than anything else here. It also suits families who want extended rear-facing without paying premium prices, and people who would rather their money went into hardware than upholstery. It is not the seat for a family whose priority is a plush ride on long journeys.

Why we love it

It scores nine out of ten on both installation methods — the only seat in this guide to manage that — because the lock-off does the belt tensioning mechanically rather than asking you to compress the vehicle cushion with your own body weight. That single design decision removes the most common source of error in this entire category. It also includes an anti-rebound bar as standard, which nothing else near this price does; the bar braces against the vehicle seat back and limits how far the shell swings back after the initial impact. Rear-facing runs to 50 lb on a ten-year shell.

Should you buy it?

Buy it if you want your money going into installation quality rather than fabric, and if extended rear-facing matters to you. The padding is good rather than luxurious and noticeably plainer than the Nuna Rava — a fair trade at the price, but a visible one if you compare them side by side in a shop. At 26.1 lb it is a fit-once seat. Britax recalled several other lines in 2026 over a carry-handle screw; the Poplar S is not among them, but check your model and serial on their recall page regardless, because the brand-wide notice will otherwise worry you.

• The easiest convertible to install here, on either method — the lock-off belt path does the tensioning for you
• Anti-rebound bar as standard, which nothing else at this price includes
• Rear-faces to 50 lb
• Ten-year life

• 26.1 lb, so it is a fit-once seat rather than one you move between cars.
• Padding is good rather than luxurious — noticeably plainer than the Rava, and less costly.
• Same manufacturer as an active 2026 recall on other lines, so check your model even though this one is not on it.

Best All-In-One

4. Britax One4Life ClickTight

Who is this best for?

The One4Life is for families who want to buy one seat and be done with the category entirely. Rear-facing from 5 lb, forward-facing harness to 65, then a booster, all on a ten-year clock — bought at birth, it can genuinely be the only seat you ever purchase. That suits people who dislike the churn of replacing gear, and families where the economics of one good seat beat three adequate ones. It does not suit anyone who needs three seats across a back row.

Why we love it

ClickTight is what makes the one-seat plan practical rather than theoretical. Route the vehicle belt, close the door, and a mechanical plate clamps it — an installation anyone can repeat, in any car, without technique or body weight. On a seat you will be moving between vehicles across a decade of family life, that repeatability is worth more than a marginal advantage on a sled. The harness is a no-rethread, so every growth adjustment is seconds rather than a dismantling job, and the rear-facing limit of 50 lb means you are not forced to turn the seat around early to buy longevity elsewhere.

Should you buy it?

Buy it if the one-seat plan appeals and your back seat is wide enough to take it. At 20.5 inches across the shoulders, three across is unlikely — measure before you commit, and look at the Graco SlimFit3 LX instead if the narrow fit is non-negotiable. We could not confirm its seat weight from manufacturer materials, so treat it as a fit-once seat until you have handled one in person. And there is a quieter cost to the one-seat approach worth naming: living with a single seat for ten years also means living with its fabric, its colour and its accumulated history for ten years.

• ClickTight clamps the vehicle belt for you — install is as close to foolproof as this category gets
• Genuinely birth to booster: rear-faces to 50 lb, then harnesses, then converts
• Ten-year life, so one seat can cover a whole childhood
• No-rethread harness

• 20.5 in across the shoulders. Three across is unlikely — check your back seat before committing.
• We could not confirm the seat weight. Assume it is a fit-once seat and check the box before you plan on moving it.
• Buying one seat for ten years means living with its fabric for ten years.

Best For Comfort

5. Nuna EXEC

Who is this best for?

The EXEC is for parents who do long journeys and want the child genuinely comfortable rather than merely restrained, and for families who want one premium seat covering rear-facing all the way through to a booster at 120 lb. It is the seat for a household where the car is where a lot of life actually happens — commutes, school runs, weekends away. It suits people who intend to keep it for the full decade. It makes very little sense for a family doing short local trips who could spend a third as much.

Why we love it

It is the most comfortable seat in this guide and it is not close. Deep padding, real shoulder and leg room, and a shell that still suits a child well past the age at which most seats begin to pinch — which is the difference between a nine-year-old who tolerates the car and one who complains for the whole journey. It installs well too, with both a belt lock-off and LATCH, so passing the LATCH weight ceiling around 35 lb is a straightforward switch rather than a job you put off. Flame-retardant-free fabrics throughout, and a rear-facing limit of 50 lb.

Should you buy it?

Buy it if comfort across a decade is worth the outlay to you. Be clear about what you are buying: comfort and longevity, not extra protection — the Clek Foonf has the more serious crash structure for less money, and the difference in padding is not a difference in safety. It is very heavy, so it goes in once and stays there; plan the car before you plan the purchase. We could not confirm its exact seat weight or expiry period from manufacturer materials, so check both on the shell label before you build assumptions around them.

• The most comfortable seat here by a distance — deep padding and real room for an older child
• Rear-faces to 50 lb, then harnesses to 65, then boosters to 120
• Belt lock-off as well as LATCH, so the switch past the LATCH ceiling is easy
• Flame-retardant-free fabrics

• Very heavy. It goes in once and stays there — plan the car before you buy it.
• We could not confirm the exact seat weight or expiry period; check both on the shell label.
• The most expensive seat in this guide, and the extra money buys comfort rather than protection.

Best Legroom

6. Graco Extend2Fit 3-in-1

Who is this best for?

The Extend2Fit is for families who want extended rear-facing without premium spending, and for anyone whose toddler has started complaining about legroom. It is the cheapest genuine route to 50 lb rear-facing in this guide, which makes it the sensible recommendation for a family who wants to do the safest thing and cannot spend four figures doing it. It also suits people who move a seat between cars occasionally, being the lightest of the mainstream leaders. It suits anyone facing a lot of seatbelt installs rather less.

Why we love it

The extension panel is a simple idea that buys real time. It pushes out to give a rear-facing child somewhere to put their legs, which removes the most common reason parents turn a seat around too early — the belief that bent legs are a problem. They are not, and leg injuries in rear-facing crashes are rare, but no amount of explaining settles that argument at the kerbside the way a physical panel does. At 20.5 lb it is the lightest of the six mainstream leaders, and the crash results are strong for the money.

Should you buy it?

Buy it if extended rear-facing on a budget is the goal. The gap is the belt installation: there is no lock-off, so once you pass the LATCH ceiling around 35 lb, getting it genuinely tight takes real effort — put your weight into the seat as you pull the belt through, and recheck it after. If that prospect worries you, the Britax Poplar S solves it mechanically for a moderate step up. We could not confirm the expiry period for this exact model, so check the date stamped into the shell before buying used. The extension panel also eats front-passenger legroom when fully out, which is worth measuring in a small car.

• The extension panel gives rear-facing legroom that genuinely buys you months
• Rear-faces to 50 lb — the cheapest route to extended rear-facing in this guide
• 20.5 lb, the lightest of the six leaders
• Strong crash results for the money

• No belt lock-off, so a seatbelt install takes more effort to get tight. Put your weight into the seat while you pull the belt through.
• We could not confirm the expiry period for this exact model. Check the date-stamped label on the shell before you buy used.
• The extension panel eats front-passenger legroom when fully out — worth measuring if you drive something small.

Best Steel Frame

7. Diono Rainier 2AX

Who is this best for?

The Rainier is for families who need three seats across a back row and are not willing to give up a steel frame to get there. That combination is genuinely rare — narrow seats are usually narrow because there is less inside them — and it makes this a short-list seat for anyone with three children in a normal-sized car. It also suits families planning to run one seat through two children, given the shell's long service life. It suits someone who wants a simple, unambiguous LATCH install rather less.

Why we love it

A steel-reinforced frame with side-impact compression walls inside an 18.5-inch shell is unusual engineering at this price. Rear-facing runs to 50 lb, so you are not sacrificing longevity for the narrow footprint, and the shell carries a long life — ten to twelve years depending on configuration. The build quality is evident in the hand: this feels like a heavier-duty object than most of what surrounds it in the price bracket, and the compression walls are a genuine structural feature rather than moulded decoration.

Should you buy it?

Buy it if the narrow-plus-steel combination is what you need, and plan around the LATCH ceiling from day one. That 50 lb rear-facing figure is only reachable on a seatbelt installation, because LATCH caps out around 35 lb in most post-2014 cars — it is in the manual, it is not a fault, and it still catches people out badly enough that we have scored the LATCH column down for it. Note also that the harness expires at eight years while the shell runs ten to twelve; the earlier date governs, and that matters if you are planning a second child. If you want narrower still, the Clek Foonf is 16.9 inches.

• Steel-reinforced frame with side-impact compression walls
• 18.5 in across the shoulders — narrow enough for three across, which almost nothing with a steel frame manages
• Rear-faces to 50 lb on a seatbelt install
• Long shell life

• The 50 lb rear-facing limit only applies on a belt install — LATCH caps out at 35 lb in most post-2014 cars. Plan to switch to the seatbelt around 35 lb; it is not a fault, but it catches people out.
• 25 lb and awkwardly shaped to carry.
• Harness expires at eight years, before the shell does — the earlier of the two is the one that counts.

Best Rotating All-In-One

8. Evenflo Revolve360 Extend

Who is this best for?

This is for parents who want a rotating seat but refuse to trade away rear-facing time to get one. Every other rotating seat in this guide stops earlier; this one does both, which makes it the answer for a family that wants the loading convenience and intends to rear-face to the limit. It suits people with back problems, tight driveways or narrow parking spaces — the situations where leaning into a footwell with a struggling toddler is the worst part of the day. It is not a seat for anyone who needs to move it between cars.

Why we love it

It turns a full 360 degrees with one hand, so you load a child standing upright rather than bent sideways over a sill, and it still rear-faces to 50 lb and 48 inches. Getting both in one seat is the whole proposition and nothing else here manages it. A SensorSafe chest clip pairs to a phone and warns if the buckle opens while the car is moving or if the cabin temperature becomes unsafe — a feature that reads as a gimmick until the first time a toddler learns to unclip themselves on a motorway.

Should you buy it?

Buy it if rotation is the feature you want and rear-facing longevity also matters to you. Rotating seats are heavy by nature and this is no exception, so decide where it lives before you fit it rather than after. We could not confirm its seat weight or width from manufacturer materials, so check both before planning three across or assuming you can move it. The rotation mechanism is also one more thing that stiffens when crumbs get into the track — wipe it out occasionally. If rear-facing time matters less to you, the Chicco Fit360 rotates just as well and installs slightly better.

• Rotates a full 360° with one hand, so you load a child standing upright rather than bent into the footwell
• Rear-faces to 50 lb and 48 in — the only rotating seat here that also does extended rear-facing
• SensorSafe chest clip warns if the buckle opens or the cabin overheats

• Rotating seats are heavy and this is no exception. Decide where it lives before you fit it.
• We could not confirm the seat weight or width; check both before planning three across.
• The rotation adds parts, and parts are what eventually stick. Keep the track clear of crumbs.

Best for Easy Loading

9. Chicco Fit360

Who is this best for?

The Fit360 is for anyone whose back protests at loading a child into a car seat, and for families parking in tight spaces where the door only opens so far. The swivel is a quality-of-life feature rather than a safety one, and it is a substantial one — the difference between dreading the school run and not thinking about it. It suits households with an adult managing a back injury, a recent caesarean, or simply the accumulated wear of lifting a growing toddler in and out of a car several times a day. It does not suit a family committed to rear-facing past 40 lb.

Why we love it

You load a child standing upright, facing the open door, instead of bent sideways over a sill and twisting at the waist. Nothing else in this guide changes the daily routine as much, and the effect compounds over the years you own it. It also installs well for a rotating seat, which is not a given — the swivel mechanism adds height and complexity that some rivals never quite resolve, leaving the seat sitting proud or the base fighting the cushion. Chicco's is properly engineered, and the seat sits where it should.

Should you buy it?

Buy it if loading is your genuine pain point. Two limits to weigh honestly. Rear-facing stops at 40 lb rather than 50, so extended rear-facing ends around a year earlier than on the Nuna Rava or Britax Poplar S — a real cost if that is your priority. And at 32.4 lb it is emphatically not moving between cars; getting it into position the first time is a job worth having someone hold the door for. If you want the rotation and the longer rear-facing together, the Evenflo Revolve360 Extend is the seat that does both.

• Spins 360° to face the door, so you load the child standing upright instead of bent into the footwell
• The rotation is the single biggest day-to-day improvement in this guide, especially with a bad back
• Installs well for a rotating seat, which is not a given

• 32.4 lb. It is not moving between cars, and getting it into position the first time is a genuine effort — have someone hold the door.
• Rear-faces to 40 lb rather than 50, so extended rear-facing ends earlier than on the Rava or Poplar S.
• You pay a clear premium over the Poplar S for the swivel. Worth it if you have a back problem or a tight driveway, not otherwise.

Best Slim Seat

10. Graco SlimFit3 LX

Who is this best for?

The SlimFit3 LX is for families who need three seats across a back row and do not want to spend premium money achieving it. It is the practical middle answer between a wide mid-market seat that will not fit and an expensive narrow one that will. It suits families with three children close in age, and anyone regularly carrying an extra passenger in the back. It also suits a household buying two or three seats at once, where the price difference multiplies. It suits a family committed to extended rear-facing rather less well.

Why we love it

Under 17 inches across with a steel-reinforced frame is a genuinely good combination at this price, and the narrow shell does not come at the cost of a flimsy structure — which is the usual compromise in slim seats and the reason many of them are worth avoiding. It converts through to a highback booster, so the useful life is long for the outlay, and three of them will physically fit across most ordinary back seats without the shoulder-to-shoulder wrestling that wider seats force.

Should you buy it?

Buy it if width is your constraint and budget matters. What you give up is rear-facing time and comfort. It stops at 40 lb rear-facing, roughly a year earlier than the 50 lb seats, and the padding is adequate rather than generous — fine around town, noticeably less so on a long motorway run with a sleeping child. There is no belt lock-off either, so the switch past the LATCH ceiling around 35 lb takes more effort than it does on the Britax Poplar S. We could not confirm its expiry period, so check the shell label before buying used.

• Under 17 in across — narrow enough for three across in most cars, at a mid-market price
• Steel-reinforced frame in a slim shell
• Converts through to a highback booster

• Rear-faces to 40 lb rather than 50, so extended rear-facing ends about a year earlier than on the Rava or Poplar S.
• Padding is adequate rather than generous — fine around town, less so on a long drive.
• No belt lock-off, so the switch past the LATCH ceiling takes more effort.

Best Crash Protection

11. Clek Foonf

Safety notice: Clek recalled Foonf and Fllo seats (models FO12–FO19) made before 21 May 2021 over a loose foam piece that posed a choking hazard. Current production is unaffected and Clek supplied a free remedy insert. Check the date if you are buying used.

Who is this best for?

The Foonf is for families who want the best-protected seat available and can accommodate its weight, and for anyone solving a three-across problem in a normal car. It is important to understand it is a second purchase made around six months, not the seat you bring a newborn home in — the minimum is 14 lb, so you need an infant seat first. That makes it a considered upgrade rather than a first buy, and it suits parents who plan their gear rather than buying it all in one panicked trip before the birth.

Why we love it

A steel frame with aluminium honeycomb crumple zones is the most serious crash structure in this guide, and the numbers follow. At 16.9 inches it is also the narrowest seat here, which is why it is the standard answer whenever three across comes up in a forum thread. Rigid LATCH forward-facing gives a fast, play-free fit with no webbing to stretch, and the anti-rebound bar stores under the base rather than living in a cupboard where it will be lost — a small piece of design thinking that says a lot about the rest.

Should you buy it?

Buy it as a second seat once your baby is past 14 lb, and not before. At 33.7 lb it is the heaviest seat here by a clear margin: fit it once and leave it, because moving it is a genuine undertaking. The nine-year life is also a year shorter than the Graco and Britax seats, which matters if you are planning to run it through two children and the second is some way off. Units manufactured before 21 May 2021 fall under Clek's foam recall and need the free remedy insert — current production is unaffected, but check the date if you are buying used.

• Steel frame with aluminium honeycomb crumple zones — the best-protected seat in this guide
• 16.9 in wide, the narrowest here, and the standard answer to three across
• Rigid LATCH forward-facing gives a fast, play-free fit
• Anti-rebound bar stores under the base rather than getting lost

• It does not fit a newborn. The minimum is 14 lb, so you need an infant seat first — this is a second purchase, not a birth-to-booster seat.
• 33.7 lb, the heaviest here by some way. Fit it once and leave it.
• Nine-year life, a year short of the Graco and Britax seats.

Best Budget And Travel Seat

12. Cosco Kids Scenera Extend

Who is this best for?

The Scenera Extend is for grandparents' cars, second vehicles, and flying. This is the seat you buy so that a car seat exists where you need one, without lugging your main seat across a city or wrestling it through an airport. It suits families who travel often, households where childcare is shared across two homes, and anyone who has ever had to decline a lift because there was no seat. It is emphatically not a daily-driver seat, and buying it as one is the mistake to avoid.

Why we love it

At 8 lb you can carry it through a terminal on one shoulder, and no other convertible in this guide can — that single fact is why it earns an award despite scoring 65. It meets the same federal standard as the premium seats, including the current side-impact requirements, which is the point worth understanding: what the price difference buys elsewhere is comfort, install hardware and convenience, not additional crash compliance. Rear-facing to 40 lb gives it a reasonable run for a travel seat, and its low weight means it barely counts against the vehicle's LATCH weight limit.

Should you buy it?

Buy it for the job it is designed for, and not as your everyday seat. Padding is minimal with no EPS liner, so it is fine for short trips and tiring on long ones — a child will notice on a three-hour drive. The install hardware is basic, so getting it tight takes more care and more physical effort, and it deserves a monthly recheck rather than an annual one. We could not confirm its expiry period, so check the shell label before buying. For everyday use, the Graco 4Ever DLX is the better buy by a wide margin.

• 8 lb. You can carry it through an airport on one shoulder, which no other convertible here allows
• Meets the same federal standard, including the 213a side-impact rules, as the premium seats here
• Rear-faces to 40 lb
• Cheap enough to leave permanently in a second car or a grandparent's

• Minimal padding and no EPS foam liner. Fine for short trips, tiring on a long one — this is the trade the low price buys.
• Basic install hardware, so it takes more care and more force to get tight. Recheck it monthly.
• We could not confirm its expiry period. Check the shell label before buying.

13. UPPAbaby Rove

Who it suits

The Rove is for families who want to keep a toddler rear-facing for as long as possible and will pay for an install that tells them when it is right. It is not a from-birth seat. The 14 lb minimum means you need an infant seat first, and it has no booster mode, so it ends at forward-facing harness use (65 lb).

What owners and CPSTs report

The SmartSecure system is the headline. Unzip the cover, route the belt through the built-in lock-off, and a tension indicator moves from red to green once the belt is tight enough. Owners say it removes the knee-in-the-seat wrestling that belt installs usually involve. Child passenger safety technicians on Reddit single out the top tether, which UPPAbaby lets you use rear-facing as well as forward-facing. They see it as a real safety gain because it limits how far the seat rotates in a crash.

The catches are physical. With the headrest in its lowest positions, the no-rethread harness is hard to tighten, and several video reviewers find you have to push the headrest down before pulling it up to adjust it. Owners mention a crotch buckle that sticks. The seat rides high and measures about 19 in at its widest, so it can block the rear-view mirror in smaller sedans. One video review shows the rear-facing tether slipping off the narrow headrests in a Tesla Model X.

Should you buy it?

Buy it for extended rear-facing and an install you can check at a glance, if your car has the room. For a narrower seat that still rear-faces into toddlerhood, the Clek Foonf is the closer fit. The Rove expires 10 years from its date of manufacture and is FAA-approved for aircraft.

• SmartSecure lock-off with a red-to-green tension indicator takes the guesswork out of a belt install
• Rear-facing to 50 lb, among the highest limits in this guide
• Top tether can be used rear-facing as well as forward-facing, which CPSTs on Reddit rate highly
• Flame-retardant-free fabric that zips off for the washing machine

• 14 lb minimum, so it cannot be a newborn's first seat
• The no-rethread harness is hard to tighten with the headrest in its lowest positions, and owners report a sticky crotch buckle
• It sits tall and wide (about 19 in), which can block the rear-view mirror in small sedans and rules it out for most three-across setups