Just like our zippered AllergyCare mattress covers, these Organic Cotton Waterproof Fitted Crib Mattress Covers offer protection from allergens and keep your mattress clean, fresh and dry. This fitted crib cover is made with super soft organic cotton jersey knit with a non-toxic food-grade micro-thin polyurethane backing that effectively prevents liquids from penetrating the mattress, without trapping body heat. When you are looking for a waterproof crib mattress protector, you want one that is soft, comfortable and will keep the mattress dry. Our organic cotton knit mattress cover is all that and more.