Waterproof sheet for baby futon size, made of a blend of 80% cotton and 20% polyester, machine washable. I have used it, and the waterproof function still works, so I think it can still be used. However, if you are concerned, I recommend purchasing a new one. - Type: Waterproof sheet - Size: Baby futon size - Material: Surface: 80% cotton, 20% polyester - Washing instructions: Washable up to 40 degrees Celsius, do not bleach