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How to Install a Combination Car Seat as a Booster Seat

Video instruction on using a combination car seat as a high-back booster seat

When your child outgrows the height or weight limits of the harness, remove the harness and use the seat as a booster. Be sure to carefully follow the instructions on how to convert your seat to a booster.

Some younger children may outgrow the weight or height limit of the forward-facing car seat with a harness but may not be ready to stay seated properly in a booster seat using the lap and shoulder belt. If this is the case, look for a harnessed car seat with higher size limits.


Converting Your Car Seat to a Booster Seat
  1. Read the manufacturer’s instruction manual for your seat and the portion of your vehicle owner’s manual on child restraint systems before you begin converting your combination car seat to a booster seat. Because every car seat and vehicle is different, it’s important to follow all instructions carefully.
  2. Follow the manufacturer’s instructions on how to remove the harness.

How to Use a Booster Seat
  1. Place the booster in the back seat of your vehicle. Make sure the booster seat fits flat on the vehicle seat.
  2. Have your child sit in the booster seat.
  3. Pull the seat belt across your child’s body and buckle the seat belt.
  4. Make sure the belt fits your child properly. If the seat comes with seat belt guides, use them to achieve good belt positioning.
    1. Adjust the lap belt so it lies snugly across the child’s upper thighs, not across the stomach.
    2. Adjust the shoulder belt so it rests across the chest.
  5. Check the fit of the seat belt often.

Best Practice

Continue using the booster seat until your child is big and mature enough to fit an adult seat belt properly. Even if the child is not present, booster seats should be secured in the vehicle at all times. When not buckled in place, the booster seat can be tossed around the vehicle causing injury to vehicle occupants during a crash or sudden stop.