Popular Purple Mermaid Art Fish Cushion Case Pillow Covers,18x18 Inch Couch Zippered Pillowcase Throw Pillow Case(Twin Sides) This custom standard pillowcase is roomy in size (18" x 18") Material: 50% cotton, 50% polyester The Front side is the same to the back side. Pillow insert are not included. It's a zippered pillow case, with a zippered opening on the side. Hidden slide fastener design for good looking! With pre-shrunk fabric, this pillowcase is washable at 60 Celsius.