Evenflo Big Kid Amp Booster Car Seat - Blue/ Black/ Grey

Model Number: 31911431C
Web Code: 10406939


Evenflo's Big Kid Amp booster car seat is designed for older kids ready to transition to using car seatbelts. Its 6-position height adjustment feature lets it adapt to your growing child, while the removable back means it can switch to a no-back booster. It features a sturdy design with energy-absorbing foam for your kid's comfort and safety.
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  • This booster car seat is meant for kids who are ready to use your car's seatbelt
  • Seat back features easy one-hand, 6-position height adjustment so it can adapt as your child grows, while ensuring side and head support remains properly positioned
  • Durable design features energy-absorbing foam and excellent structural integrity for added safety and comfort
  • Removable back allows it to transition easily to a no-back booster seat
  • Padding around the head and body ensures your child is comfortable, even on long journeys
  • Equipped with convenient cup holders, perfect for holding a juice box or a snack
  • Pad is machine-washable for easy cleaning
Car Seat Type
2-in-1 High-back to Backless Booster
Car Seat Orientation
Rear-facing Car Seat
Forward-facing Infant Car Seat
High-backed Booster Seat
Backless Booster Seat
Harness Points
Base Material
Compatible Strollers
Not Applicable

Safety Requirements

Minimum Seat Weight Capacity
18 kg
Maximum Seat Weight Capacity
49.8 kg
Minimum Child Height
102 cm
Maximum Child Height
145 cm
Weight Capacity:Front Facing(Min)
18 kg
Weight Capacity:Front Facing(Max)
49.8 kg

Popular Features

Cup Holder
Removable Seat Cushion
Washable Fabric
Detachable Base
Side Impact Protection
LATCH System
Snack Trays
Aircraft Certified
Blue; Black; Grey
Country of Origin
United States


8.61 cm
13.04 cm
7.48 cm
5.3 kg
  • Car Seat
  • French & English Manual

  • Super easy to install
    by Busymomof3boys

    on December 7, 2019

    My son has this booster seat and he loves it. It very easy to install in the car. Our family loves it because we have several cars so it’s easy to move around. This booster is light weight which I love. It has a nice soft material in it. The material washes well.

    Review originally posted on evenflo.com

  • Light and budget friendly
    by Neech83

    on November 8, 2019

    When my son was ready to transition to a booster seat, I had to find one that could fit three across in my Nissan Altima since I have two younger kids in infant seats and convertible car seats. This seat fit perfectly! It is one of the most narrow boosters I was able to find, yet my son who is in the 90th percentile at 7 years old fits excellent in it and says it is very comfortable. We have two cars so switching the seats between the cars has always been a chore that neither my husband or I like to do, but this seat is so light that it is a breeze to move. I am definitely very happy with my choice and so is my son and my wallet!

    Review originally posted on evenflo.com

  • Car seat

    from Ottawa, Ontario on July 24, 2019

    Grandson loves his big boy car seat . We like the cup holders . He seems well protected in it.

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