AllerZip Waterproof Bed Bug Proof Pillow Protector by Protect-A-Bed, King Pillow Size (21x37 in.), Pack/2 2 Terry Waterproof King Size Pillow Protectors size 21" x 37". Terry cotton surface. Cool and comfortable to sleep on, breathable, waterproof, absorbent. Ultimate allergy protection, Certified by Entomology Laboratories to be Bed Bug entry, escape and bite proof. Superior protection against bedwetting. Dust mite barrier. Complete protection for a healthy, allergy free sleep zone. Protects against allergens such as pet dander and pollen. Air vapor porous, waterproof and absorbent. Protects pillow from all liquid stains. Dust mite barrier and allergy protection Cool and comfortable to sleep on