Protect-A-Bed BugLock Mattress Encasement, The Protect-A-Bed reg BugLock Mattress Encasement features a unique 3 side zipper system with a SecureSeal which eliminates spaces exactly where bugs could enter. It's polyurethane and polypropylene exterior lining lock in irritants that create a waterproof surface. This encasement is independently tested to eliminate bed bugs from bedding and is machine washable. BugLock Mattress Encasement Mattress Encasement, Polypropylene Exterior, BugLock reg 3 Sided Zipper - Innovative Secure Seal reg - Eliminates Spaces Where Bugs Could Enter, Allergy Proof, Polyurethane Lining Lock, Air Vapor Porous, Absorbent and waterproof, Non Woven, Machine Washable Tumble Dry Fabric, Superior Protection Against Bedwetting