What You Can Get: 100% Cotton Pillow Protectors with Hidden Zipper, 600 thread count (Queen, 20"x30", 4-Pack, Striped Dark Grey) CERTIFIED STANDARD 100 by OEKO-TEX: Our pillowcases are OEKO-TEX STANDARD 100 certified, ensuring they meet rigorous safety and sustainability standards. This certification means our products are tested for harmful substances. Each fabric batch undergoes durability tests for pilling, shrinkage, and colorfastness 600 Thread Count Egyptian Cotton Fabric: Our cotton pillow protectors are made of the finest quality cotton, free from harmful chemicals. The quality is superior and long lasting than polyester or microfiber fabric. The cotton pillowcases are carefully stitched and the invisible zipper won't touch your skin Pillow Protectors with Secure Hidden Zippers: Provide a invisible zipper to protect your pillows from stains, dust and unwanted deposits.It also prevent the pillow from sliding out Easy-Maintenance Pillow Covers: Our pillow covers are wrinkle-resistant and easy to clean, maintaining their shape even after repeated washing. Simply toss them into the washing machine for a hassle-free cleaning experience. The pre-wash process makes the fabric excellent softness and can get softer after every wash 100% Cotton Classic Pillow Protectors with Invisible Zipper, 600 Thread Count Sateen Weave Soft and Breathable Pillow Cases, Protect Pillows from Dirt, Dust and Debris (Queen, 20"x30", Set of 4)