Protect-A-Bed AllerZip Smooth Mattress Encasement, Full Sofa Bed (54x72) Polyester Bed Bug Proof: Certified by Entomologists to be bed bug bite, entry and escape proof. Waterproof: Polyurethane film backing repels liquids like urine & sweat. Breathable Barrier Fabric: Guaranteed NOT hot to sleep on. Allows body vapor to breathe through protector. Dust Mite and Allergy Barrier: Miracle membrane backing provides a healthy sleep zone for your family and inside allergy flap blocks allergens from escaping through zipper. Easy to Wash and Use: Machine washable in warm or hot water. Tumble dry on medium heat. Do not bleach or dry clean.