The National Highway Traffic Safety Administration recommends that no heavy or bulky clothes be worn by a child when secured in their car seats. Doing so prevents the snug fit of the harness belt and compromises the child's safety. Parents should avoid using bunting or car seat covers that thread through the harness straps of their child's car seat as doing so can interfere with the proper function of the car seat. Tivoli Couture's Car Seat Jacket goes over the car seat so there is no fabric between the car seat and the baby. Center zipper opens completely like a jacket for easy access to the child. The cover is very thick and well insulated for extra warmth and coziness. Made of wind and water-proof material and cozy fleece. Integrated collar shields from wind and elements. Elasticized edges for snug and comfort fit. Fits infant car seats and some strollers. Warning!!! The child must be properly buckled in a car seat before Tivoli Couture's Car Seat Jacket is put on.