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UPPAbaby Knox Convertible Car Seat/Rear Facing and Forward Facing/Intuitive Safety & Alta High Back Booster Seat/Seven-Position, Active Support Headrest

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Availability: 11 left in stock
Fulfilled by Amazon

Arrives Monday, Dec 9
Order within 42 minutes
Available payment plans shown during checkout

Color: Bryce (White and Grey Marl)


Pattern Name: Car Seat + Headrest (Black Mélange)


Features

  • Product 1: GROWS WITH YOU: The Knox Convertible Car Seat is for kids ages 16 yrs old, with rear-facing (1445 lbs) & forward-facing (2565 lbs) modes. The no-rethread harness, 8 position headrest, & 4 position recline adjust as your child grows.
  • Product 1: SAFETY YOU CAN SEE: Our unique SmartSecure system technology, utilizing a tightness indicator & robust tension clips, provides a visual guide to aid in achieving a correct installation. Color-coded seatbelt paths make installation easy to understand.
  • Product 1: CHEMICAL-FREE CHOICE: The Knox features both our SafeTech & PureTech fabrics & foam that are fire retardant chemical free. The Jordan & Gregory fashions, made with Merino Wool, keep kids cool on hot days, warm on cool days.
  • Product 1: TETHER THEM BETTER: The Multi-Directional Tether reduces seat rotation & stress on the head & neck during an impact & is strongly recommended with rear & forward-facing installations. When rear-facing, the Tether can reduce injury potential by 45%.*
  • Product 2: EFFECTIVENESS OF HIGH BACK: High-back boosters provide enhanced safety features by ensuring optimal body positioning that helps absorb impact and better protect the head and torso.
  • Product 2: PROPER FIT EVERY TIME: Our unique SecureFit belt routing system with lap belt positioner ensures proper fit for the lap and shoulder belt while preventing submarining.
  • Product 2: LOCK IN SECURITY: Rigid LATCH connectors secure the booster to the vehicle seat guaranteeing proper alignment and positioning for everyday use.
  • Product 2: GROWS WITH THEM: The seven-position, Active Support Headrest accommodates growing children. The Alta is suitable for children from 40100 lbs, and 3857 in height.

Brand: UPPAbaby


Installation Type: Latch


Color: Bryce (White and Grey Marl)


Orientation: Forward Facing, Rear Facing


Maximum Weight Recommendation: 65 Pounds, 100 Pounds


Maximum weight recommendation: ‎65 Pounds, 100 Pounds


Maximum height recommendation: ‎57 Inches


Style: ‎BRYCE


Number of reclining positions: ‎7


Orientation: ‎Forward Facing, Rear Facing


Forward-facing maximum child weight: ‎65 Pounds


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Dec 9

Yes, absolutely! You may return this product for a full refund within 90 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


  • It’s so sturdy but so big!!
Color: Noa (Navy Melange) Pattern Name: Car Seat
I love it and my baby loves it. He’s so comfortable in his new seat! I love how safe and secure it is for him. I was not expecting it to be as big as it is but I have a jeep grand Cherokee and it fits well!
Reviewed in the United States on January 18, 2024 by Gabrielle

  • Be mindful of size
Color: Jake (Black Melange) Pattern Name: Car Seat
This product was very sturdy and fits within the uppababy brand well that we’ve come to love. Unfortunately this was just too large for our conventional family sedan. It was quite large for our Honda accord which made install a hot mess and It blocked the entire rear passenger window due to the high back design so we had to return it so if you have a small vehicle, I’d look elsewhere but I’d you have a larger car or big suv. This will work just fine for you ... show more
Reviewed in the United States on July 30, 2023 by Lizabeth Thompson

  • 10/10 !
Color: Bryce (White and Grey Marl) Pattern Name: Car Seat
Fastest installation I’ve ever done! Took under ten minutes by myself watching an instal video. I placed the seat in the 2021 Tiguan and there’s plenty of space for other backseat passengers. This was purchased for my 3 1/2 year old (size of 4 year+) and I believe this car seat will last until Kindergarten years. This car seat is built solid and I feel extra secure with the Koroyd Technology. Shipping was extremely fast, and overall I would 10/10 recommend. ... show more
Reviewed in the United States on April 13, 2021 by Cait Cait

  • Great car seat
Color: Jake (Black Melange) Pattern Name: Car Seat
Love this car seat
Reviewed in the United States on August 26, 2023 by Janine V

  • Wanted to love it
Color: Bryce (White and Grey Marl) Pattern Name: Car Seat
We wanted to love this car seat SO badly. We had to replace our car seat after an accident and love all of uppababy’s strollers and thought, hey, if insurance is covering it let’s try a more expensive car seat! A few thoughts: 1. This thing is HEAVY DUTY. I was really excited and it wasn’t too difficult to install or take apart. Lots of zippers and velcro which I found easier than the hooks we usually have (our other car seat is a Graco extend2fit and will be switching back to it). 2) it’s a beautiful car seat, if that’s something important to you. 3) love that it tells you if the lapbelt is tight enough. Probably my favorite feature. 4) REALLY high up! Great for my husband’s model y, but not so great for my Corolla. I couldn’t get this thing in my car if I tried. 5) comfy for SHORT trips (less than an hour) Now for the biggest con: My son (4) is used to his car seat. We travel often, we frequently drive for 4-5 hours at a time, sometimes more, and he has never ever complained about being uncomfortable. We even got an inflatable footrest for this car seat just in case since he’s used to his graco having one. 1 hour into sleeping in his car seat he woke up SCREAMING that he was uncomfortable and couldn’t sleep. This happened every hour until we got to our destination. I thought it was a fluke and on the way home, I made sure to have him stretch every 2 hours- nope. Same thing happened. We had to stop and hold him until he calmed down. My kid is super easy going and never ever complains about stuff like that. Very disappointed in this car seat and will be returning ASAP! ... show more
Reviewed in the United States on September 5, 2022 by Amazon Customer

  • Heavy but great quality
Color: Jake (Black Melange) Pattern Name: Car Seat
Despite the weight this car seat isn’t too difficult to install. I appreciate the low tox elements and the reclining feature. My son sits comfortably on it though again the only hurdle is carrying it as it is huge!
Reviewed in the United States on January 30, 2024 by elizabeth

  • So comfortable
Color: Jake (Black Melange) Pattern Name: Car Seat
We tossed between this one and the britax car seat and went with the britax instead. We used it 3 times and our daughter threw up every time we put her in it. So we sent it back and bought this uppababy seat and it’s wonderful. A world of difference. It just looks so much more comfortable. And the safety features are practically the same. If you’re tossing between the two, go with this one ... show more
Reviewed in the United States on June 23, 2021 by GmoneySparkles

  • Exactly what we needed
Color: Bryce (White and Grey Marl) Pattern Name: Car Seat
This for sure is comfy for our little one and exactly what we needed. It's easy to install and clean.
Reviewed in the United States on May 27, 2022 by D.O.

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