Here’s how to test whether your child’s coat is too bulky for their car seat:
Step 1: Put the coat on your child, sit them in the car seat, and fasten the harness. Tighten the harness until you can no longer pinch any of the webbing with your thumb and forefinger.
Step 2: Without loosening the harness at all, unclasp it and remove your child from the car seat. Take your child’s coat off, put your child back in the car seat, and buckle the harness straps, which should be adjusted just as they were when the child was wearing the coat.
If you can pinch the webbing between your thumb and forefinger now, the coat is too bulky to be worn under the harness, Thomas says.
