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Britax

Britax One4Life Slim All-in-One Car Seat, 10 Years of Use, 17.5” SpaceSaver Design, Converts from Rear-Facing Infant Car Seat to Forward-Facing Booster Seat, ClickTight Installation, Mineral Gray

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Availability: In Stock.
Fulfilled by Amazon
Arrives Thursday, Oct 30
Order within 4 hours and 25 minutes
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Color: Mineral Gray


Style: One4Life Slim


Features

  • All-in-One Car Seat: One4Life(R) Slim is a convertible and harness-2-booster seat in one! It easily converts from a rear-facing infant and toddler seat (5-50 lbs.) to a forward-facing seat (30-65 lbs.) to a high-back booster seat (40-120 lbs.)
  • ClickTight(R) Installation: Install with confidence in 3 easy steps: pinch to open, thread and buckle, click it closed!
  • SpaceSaver(TM) Design: Slim outside, spacious inside! The 17.5 seat is designed to fit 3 across without compromising on trusted Britax safety and premium comfort *Britax cannot guarantee 3-across installation fitment in all vehicles
  • Premium Car Seat Cover: Features a soft knit fabric with woven melange accents that are made from recycled polyester; the cover is safe to machine-wash and dry and naturally flame retardant with no added FR chemicals
  • Trusted Britax Safety: Features a patented V-shaped tether, SafeCell(R) technology, a high-strength steel frame, and two layers of energy management
  • Comfortable Rides: This slim car seat includes soft comfort pads, built-in mesh cooling channels, three infant inserts, plush padding, and a tag-free headrest
  • Easy to Adjust: The 15-position no-rethread harness and headrest adjust together easily with one hand, and the 9-position recline has an easy-read indicator to help you find the correct angle for your vehicle
  • Slide-Out Cup Holders: The dishwasher-safe cup holders slide out with ease for convenient cleaning and click back into place for a secure attachment during rides
  • Accessible Color-Coded Belt Paths: Make it easy to route the seat belt through the correct path for each car seat mode
  • Hassle-Free Cleanup: Extra space between the shell and base means you can clean under the seat with ease and with minimal grooves in the seating area and base, you can wipe it down with no fuss

Description

The One4Life(R) Slim all-in-one car seat takes your child from birth to big kid with trusted Britax safety, ClickTight(R) installation, and a slim SpaceSaver(TM) design. As a convertible and harness-2-booster seat in one, it grows with your child for 10 years. It starts rear-facing with an extended capacity of up to 50 lbs., so your child can ride rear-facing longer. It easily converts to forward-facing toddler mode (up to 65 lbs.) and high-back belt-positioning booster mode (up to 120 lbs.) when your child is ready. With a slim outside and spacious inside, the 17.5” seat is designed to fit 3 across without compromising safety and comfort. ClickTight helps you install with confidence, every time. The base and shell are easy to wipe down for hassle-free cleanup. The car seat cover is safe to machine wash and dry, and it’s naturally flame-retardant with no added FR chemicals. One4Life Slim features a high-strength steel frame, a SafeCell(R) crumple zone, and a V-shaped tether. As your child grows, you can easily adjust the 15-position no-rethread harness and headrest with one hand. With cooling channels, premium padding, three infant inserts, and built-in armrests, your child will love every ride. Britax cannot guarantee 3-across fitment in all vehicles.

Brand: Britax


Installation Type: Seat Belt


Material: Alloy Steel, Plastic


Color: Mineral Gray


Orientation: Rear and Forward Facing


Product Dimensions: ‎18.5 x 17.5 x 24.5 inches


Item model number: ‎E1D437B


Minimum weight recommendation: ‎5 Pounds


Maximum weight recommendation: ‎120 Pounds


Minimum height recommendation: ‎18 Inches


Maximum height recommendation: ‎49 Inches


Material Type: ‎Alloy Steel, Plastic


Material Composition: ‎Plastic and Steel


Care instructions: ‎Machine wash and dry cover


Style: ‎One4Life Slim


Number of reclining positions: ‎15


Batteries required: ‎No


Orientation: ‎Rear and Forward Facing


Rear-facing maximum child weight: ‎50 Pounds


Forward-facing minimum child weight: ‎30 Pounds


Forward-facing maximum child weight: ‎120 Pounds


Harness type: ‎5-Point


Item Weight: ‎28 pounds


Country/Region of origin: ‎China


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Oct 30

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Similar Products

Top Amazon Reviews

    • Love Britax!
Color: Parchment Style: One4Life Slim
This car seat is incredible. After moving up from an infant car seat, we started with the rotating Chicco car seats and the rotating feature was the only thing I liked. It never felt fully secure, and at just 14 months my LO’s legs were already scrunched up. The steal frame seat on the Britax makes me feel so confident in my baby’s safety. The installation is so quick you’d think you did it wrong if it wasn’t for how secure it felt. The padding is so plush and comfortable. It’s ridiculously easy to adjust as your baby grows and it automatically adjusts the straps as well as the back of the seat at the click of a button. So easy to tighten and loosen to get LO in and out. I also appreciate the removable cup holders to ensure you truly can fit multiple car seats across your back seat bench. Lastly, and yes least important, the color is gorgeous. Truly the only thing that could make it better is a rotating feature but from my obsessive research, they seem to notably feel less secure. I’d rather my babe be safe at the slight inconvenience for me getting him in. I’d say the value for price is incredible. ... show more
Reviewed in the United States on July 1, 2025 by MC
    • The Best Car Seat on the Market!
Color: Glacier Graphite Style: One4Life
I recently purchased my second Britax One4Life car seat for my little one after we were in a car wreck and I am absolutely thrilled with the outstanding quality and features it offers. This car seat has truly exceeded my expectations. We will never buy a different car seat again. First and foremost, safety is paramount when it comes to a car seat, and this product delivers on that front exceptionally well. The robust construction and the advanced safety features provide me with the peace of mind that my child is secure and protected while on the road. The easy-to-adjust harness and side-impact protection are notable features that add an extra layer of safety. Installation was surprisingly straightforward. The clear and detailed instructions, along with the user-friendly design, made it a hassle-free process. The ability to securely fasten the seat with both the LATCH system and seatbelt ensures a snug fit, and the stability of the car seat is evident once installed. By far the easiest car seat to take out and install. The adjustable recline feature is a game-changer, allowing for a customized and comfortable seating position for my little one, whether they're napping or enjoying the scenery. The versatility of this car seat is impressive. It accommodates a wide range of ages and sizes, meaning it will be a reliable companion for years to come. The ability to easily transition between rear-facing and forward-facing positions is a convenience that adds to the overall value of the product. ... show more
Reviewed in the United States on November 15, 2023 by Chris
    • Highly recommend
Color: Jade Onyx Style: One4Life
Review Image by artzone artzone
I just purchased this car seat. First off How it looks: beautiful love the style comes in many colors and styles i did the one 4 life click tight ( it is actually true it installs tightly). Supper soft and easy to follow instructions. What features: well I purchase this for easy installation and it also looked very comfortable too when it arrived it had many cushions and air netting on the sides for to breath. Side button with one push and easy to adjust tilit It was easy to find the buttons all labeled side and under the seat. Pros: easy to read and understand, easy to adjust and installation was a breeze. Once installed correctly it dosent move at all very impressive as I have had many car seats and they always move a little even once installed correctly this one was zero movement highly recommend for safty. Con well I don't really have any yet it is so far everything I hoped for. So weight: well it is on the more heavier side but it's not any heavier than Carring a baby carrier with base. It is solid to carry and solid once buckled. Other qualities it also is approved for other transport such as a plan if you wish to fly. What I love is the tilt feature and how it grows with your child, easy to install and read direction on the car seat visible and it is in two languages. The cushions for the head is very comfortable. Highly recommend for baby on up however I already pass the baby stage carrier and purchase this after my child was already one. It can even use for infants up to 10 years old Again highly recommend ... show more
Reviewed in the United States on February 21, 2025 by artzone artzone
    • A monster of a car seat but very solid
Color: Glacier Graphite Style: One4Life
We bought this car seat for my first son (born March 2022) and all of the hospital staff were very impressed by how well constructed it is (he had to pass the car seat test after NICU admittance day 2 for jaundice). Purchased it again for our second son due December (couldn't pass up the July sale). It fit well in my small SUV (Subaru Crosstrek) and fits about the same in our mid-size SUV (Subaru Ascent) using a foam squat pad cut in half against the back of the seat since the seats angle down (necessary to achieve proper angle for squishy newborn, not necessary for toddler or once baby has trunk control). It's not "easy" to remove and re-install but it's also fairly straightforward once you do it the first time to manage the ClickTight. It is a large and heavy seat. We used a buckle carrier from birth since this is clearly not the kind of car seat you take out and click into a stroller but that was by choice - I didn't want him in the car seat any more than necessary as a squishy newborn due to possible positional asphyxiation. First son is still rear-facing, still maximally reclined (long torso and shorter legs haha), falls asleep in it on the regular, has slept in it for 2 hours on a recent road trip which speaks to its being pretty comfortable. ... show more
Reviewed in the United States on August 16, 2024 by Rebecca Crowe
    • Great product!
Color: Cool Flow Carbon Style: One4Life
Great grow with me car seat! Easy to adjust as they grow, cup holders remove easy for cleaning as dot he cushions. Easy install and to move form car to car if needed. Rear and front facing for when they get bigger, Britax has been good to us as a family!
Reviewed in the United States on May 29, 2025 by Kelsey H

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