Wearing a bulky coat makes your baby's car seat harness fit too loosely. (howtoadult.com)
It's made of seat - belt material and works like a 5 - point car seat harness. (bestcarseathub.com)
If you plan to keep baby's coat on while traveling, you must choose a thin winter coat that will not interfere with proper car seat harness adjustment. (thespruce.com)