SOMNUS Sleep Mattress Protector, Twin XL Size, Hypoallergenic, Waterproof Cotton 100% Waterproof repels all liquids including bodily fluids, accidental spills and more Hypoallergenic protection against: mold, mildew and allergens Breathable Fabric - 100% Polyester Fitted sheet style features deep pockets for a smooth, secure fit on mattress depths up to 14"