Waterproof liner that has EZ-Dry fabric ensures that your child stays in a dry area since it works by removing moisture. Designs that are waterproof tend to capture leaks from the diapers, wet bathing suits, or even spills resulting from accidents during potty training. The Britax Seat Saver is designed to ensure that the car seat remains clean and free from being soiled. Further, the Seat Savers ensure that spills and debris are contained by fitting deeply into the sides of the seats. They are crash tested and recommended for use with Britax Car Seats. In fact, they are compatible with numerous brands.