Our allergy relief bedding is designed specifically to prevent dust allergens from becoming airborne * The membrane-free tight-weave construction prevents dust allergens and pet dander from becoming airborne * No membrane means the most comfortable and cool night?s sleep and allergy relief * All of our covers are laboratory tested and efficient against dust allergens and pet dander * Zippered Mattress Cover * Twin 39 x75 x9 * Six gauge vinyl * Heavy Duty and durable * One cover per package * 100% Waterproof * Fire retardent * Notice to California Consumers: WARNING: This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm *