Hygea Natural Standard King Size Pillow Encasement 21" x 37", 2 Pack Laboratory tested and 100% certified bed bug and allergen-proof. Plush cover fabric ensures the highest level of comfort. Water-resistant material protects from all leaks and spills (blood stains, urine stains, sweat stains) that may occur. Machine washable in temperatures below 140 degrees. Never use bleach. Locking zipper and had stitched flap ensure security. Certified bed bug and allergen-proof. Waterproof material. Machine washable. Plush Fabric. Stretchable pillow encasement. Inter-locking zipper. Note: Never use bleach.