I’ve heard lots of feedback online about the Car Seat Poncho and it’s all been positive, so I wanted to see what all the buzz was really about. The Car Seat Poncho is a straightforward solution for parents who want to keep their children safely warm in a car seat. A thick jacket worn under a harness can compress in a crash and leave the harness loose. A loose harness can mean ejection for the child. With a product like the Car Seat Poncho, there’s no need for a thick jacket underneath; your child will stay toasty and snug in the harness.