From National Allergy® BedCare, this mattress cover features:  The BedCare Classic dust mite and the mold-impermeable mattress cover is made of a lightweight polyester knit fabric bonded to an ultra-thin, allergen-proof ComforTech polyurethane membrane that makes this a waterproof cover as well. Because of its barrier membrane, this protective cover cannot be measured in terms of mean pore size though It is nearly zero! The soft, satin-like fabric stretches as you move for supreme comfort, making this an excellent allergen cover for your bed. Zipping your mattress into this encasement provides total protection on all sides with no gaps or openings. Made with our patented BugShield system with an auto-lock zipper that will not backtrack when closed BugShield Bug Blocker is an added barrier that closes the last inch or so of the zipper from below to create a fabric shield under the zipper closure to doubly ensure that bed bugs will not be able to get in or out of the encasing Fits mattresses up to approx. 15" Machine washable and dry-able Lifetime warranty Sizing: twin approx. 75" x 39" twin extra-long approx. 80" x 39" full approx. 75" x 54" queen approx. 80" x 60" king approx. 80" x 78" Imported.