Preserve the life of your pillow and control nighttime allergies Don't let bed bugs, dust mites, pet dander, bacteria and other allergens ruin you night. The fabric in these premium pillow covers has a pore size of 3-4 microns to effectively block bed bugs, dust mites and allergens from getting through. The envelop Closure eliminates any openings so that bed bugs can't slip inside. Nighttime allergy relief has never been this easy! In addition to providing allergy and bed bug protection, these pillow Covers help extend the life of your pillows by shielding them from saliva, perspiration, liquids, stains and basic wear and tear. Featuring 210 Thread Count 100% cotton material, our pillow covers are durable, breathable and soft for maximum comfort. Why Small Pore Size Matters Small pore size = better protection. The best pillow Covers feature tightly woven fabric with a pore size of under 10 microns. Why? Because the average dust mite is 10-40 microns. This means that allergen barriers with a mean pore size of under 10 microns are most effective at reducing dust mites from penetrating the barrier. Our 210 Thread Count pillow Covers have a pore size of just 3-4 microns for ultimate protection. Perfect Fit Sizes Our premium pillow Covers are available in Standard, Queen and King to fit almost any pillow. Easy Care Incredibly easy to care for! Machine wash before use. Use only non-chlorine bleach if needed. Tumble-dry, remove promptly. We recommend washing your pillow Covers quarterly.