The Noggin Nest have a raised "donut" inside if you will that helps keep babies head nice and round and prevents to much pressure on one spot in the back. This can be used in the
- Infant Carrier
They also have slits right where the belts should be positioned so you don't have to worry about this product interfering with your safety belts and they snap into place.
This product gets 2 thumbs up from me. I have used it with 2 of my babies and LOVED IT.. Way better than rolling up wash clothes to keep their heads in place.