! Everest Poly Zip Encasement Twin XL (39"x80")(fits 9"-12") 100% Bed Bug Proof, Dustmite Proof, Hypoallergenic Easy Installation, Premium Zippered Six-Sided Cover Machine Washable EVEREST SUPPLY POLYZIP Mattress/ Box Spring Encasement 100% Stretch Knitted Polyester Micro Filament Fabric. Not Vinyl, Plastic or other cheaper material. Premium Zippered Six Sided Cover TWIN XL Mattress/ Box Spring Encasement depth 9"(fits 9"-11") size (39"x80"). STRETCHABLE STRONGER Fabric on All Six Sides: Top, Bottom and all other Four Sides along with PREMIUM THREE SIDED ZIPPER, makes this protector/ cover Extra Durable . DOUBLE SIDED USE Since Top and Botton layers have same Fabric, it's easier to flip the mattress as desired without changing the Mattress encasement side. NO CRACKLING NOISE & HYPOALLERGENIC, ideal for anyone who is allergic to lamination as this protector is not PU laminated, hence peaceful super quiet sleep anytime..COMFORTABLE, SOFT & BREATHABLE. Despite the strong durability of our material, it is soft to the touch and noiseless, making it ideal for light sleepers. Our encasing guarantees high air and water vapor permeability so itll feel as if you never placed anything on your mattress. VELCRO PATCH at the Premium Zipper end which prevents bedbugs from entering or escaping. The package will say 9" depth, but it will stretch to fit up to 12" depth Mattress due to 100% Stretch Knitted Polyester Fabric. 100% BEDBUG PROOF, Hypoallergenic & Machine Washable. Recommended for people with Allergies, Asthma, Respiratory Conditions, Eczema. HOTELS, MOTELS, RESORTS, Bed & breakfast, nursing homes, hospitals, homes, apartments, rentals & many more useful places. Encasement cover is fully Machine Washable in cold-warm water & Dryable with tumble dry low heat dryer temp. cannot exceed 115*F, cannot use bleach or be ironed.