Set of 2, 100% Woven Acetate Polyester Laminated Pillow Protector Waterproof Allergen Protection with Zipper (King - 20" X 37") 100% Woven Acetate Set of 2, Woven Acetate Pillow Protector with Zipper. Waterproof Hypoallergenic, Antimicrobial and Allergen Protection with Zipper. Great for homes with Kids, Pets, Allergies, Asthma, and Eczema Because it's Water Proof and Protector dust mites King Size : 20" x 37" Easy to Wash and Use: Machine washable