Waterproof Barrier Our premium mattress encasement features impermeable TPU backing that provides protection on all 6 sides of the mattress. This makes it ideals for most situations such as when you want to protect your box spring mattress from perspiration stains or from other bodily fluids and incontinence. The TPU backing (polyurethane membrane) is not only waterproof but also breathable. This allows heat and moisture to breathe through while blocking off stains and liquids from the mattress. TPU backing ensures that you won't hear a plastic noise when you move during the night, while the soft top provides you with unparalleled comfort. Zippered Encasement Our zippered premium mattress encasement completely encloses the mattress, acting like a protective layer over the top, bottom, and sides of the mattress. Once the mattress is encased, nothing will be able to enter the mattress. Our escape proof mattress encasement features a zip guard to ensure the zipper is tightly and completely sealed. Care Instructions Hand wash or machine wash separately in cool to warm water, using a mild detergent (free from any bleach). Make sure your premium mattress encasement is unzipped with waterproof backing facing in. Please do not use any solvents or bleach, bleach alternatives, non-chlorine bleach or any bleach by-products in the detergent, as this will damage the waterproof backing.