Protect-A-Bed AllerZip Smooth King Size Asthma and Allergy Friendly Pillow Protector with Zipper Closure - 21" x 37"
100% Cotton Pillow Protector – Lincove
Guardmax Bulk King Pillow Protectors with Zipper, Bed Bug & Waterproof Pillow Covers (King - 20x36- Set of 12) - Walmart.com
Amazon.com: 100% Cotton King Pillow Protectors with Zipper, White Pillow Cases King Size for Home & Hotel, Sateen Soft Cooling Hidden Zippered Pillow Pillow Case Protector for Hair & Skin, 20x36 in,
Bamboo Terry Waterproof Pillow Protector with Zipper – Moonsea