Sufdari Waterproof Fitted Sheets are truly 100% waterproof on the front of the mattress protector using advanced waterproof technology. The sides of the protective cover are made of soft and comfortable polyester fabric (not waterproof), which allows your mattress to breathe and stay dry and extend the life of your mattress. This is enough to deal with all kinds of emergency situations, such as baby wetting wetting and pet accidents, seniors with disabilities, accidentally flipping the drink.Get rid of expensive mattresses.