All-In-One Car Seats FAQs

• My One4Life car seat cover keeps slipping off. What should I do?

  We understand it can be frustrating when your seat cover doesn’t stay in place. Here are a few things to check:

  • Sometimes the cover can shift if it’s not attached correctly, so follow the applicable next step(s):
    • Check the attachment points: The One4Life cover attaches using either small plastic tabs or elastic loops. If a tab has broken or a loop has worn out, the cover may not stay secure.
    • Tuck the fabric securely: Make sure the fabric around the headrest is tucked fully into the shell. Sometimes the cover can shift if it’s not attached correctly.
    • Reattach the cover correctly:
      • Loosen the harness for extra slack.
      • Tuck the cover tabs or loops into the proper channels.
      • Ensure straps and adjusters are threaded through the correct openings.
      • Press firmly so the tabs/loops “lock” into place.
  • If the cover is damaged or still slipping, call or email Britax Customer Service directly with your seat’s serial number to review warranty options.
• What are the weight and height limits for the Britax® One4Life® Slim in rear-facing mode?

  Use rear-facing for children who weigh between 5 and 50 lbs. (2.3 and 22.7 kg) and whose height is 18-49 in (45.7-124.5 cm).

• What are the weight and height limits for the Britax One4Life Slim in forward-facing harness mode?

  Use forward-facing with a harness for children who weigh between 30 and 65 lbs. (13.6 and 29.5 kg) and whose height is 35-49 inches (88.9-24.5 cm).

• What is the weight limit for using the lower connectors of the LATCH system to install the One4Life Slim REAR-FACING?

  Do not use the lower connectors of the LATCH system to install the One4Life Slim after the child weighs 35 pounds.

• What is the weight limit for using the lower connectors of the LATCH system to install the One4Life Slim FORWARD-FACING?

  Do not use the lower connectors of the LATCH system to install the One4Life Slim (in harness-mode) after the child weighs 40 pounds.

• When can my child use the Britax One4Life Slim in booster mode?

  Use in booster mode only with children who weigh between 40 and 120 lbs. (18.1 and 54.4 kg) and whose height is between 44 and 63 in (111.8 and 160 cm). Britax strongly recommends children should ride in harness mode until they exceed the weight or height limits specified.

• What are the weight and height limits for the One4Life in rear-facing mode?

  Use rear-facing for children who between 5 and 50 lbs. (2.3 and 22.7 kg) or until the child’s head is 1 inch (2.5 cm) below the top of the headrest. The height range for rear-facing mode is from 18 to 49 in (45.7 to 124.5 cm), ensuring that the child remains within the safety limits for optimal protection.

• What are the weight and height limits for the One4Life in forward-facing harnessed mode? 

  Use forward-facing with a harness for children who weigh between 22 and 65 lbs. (10 and 29.5 kg) and whose height is 49 in (124.5 cm) or less.

• What are the weight and height limits for booster mode on the One4Life?

  The booster mode is suitable for children who weigh between 40 and 120 lbs. (18.1 and 54.4 kg) and whose height is 44 to 63 in (111.8 to 160 cm).

• How should the harness straps be positioned in forward-facing mode on the One4Life?

  The harness straps should be positioned at or just above the child’s shoulders. The top of the child’s ears should remain below the top of the headrest.

• When should I remove the infant position pillow on the One4Life car seat?

  The infant insert can be used with infants weighing 20 lbs. (9.1 kg) or less. Do not use with infants weighing more than 20 lbs. (9.1 kg).

• What is the proper recline position for booster mode on One4Life?

  Use only the "B" recline position when the car seat is in booster mode.