Flat Sheet T180 King 108X110, 12Pk Advantage linens are Oeko-Tex certified and can go from box to bed without laundering. A blue hem thread allows for quick identification of this King sheet. The 1888 Mills Advantage Flat Sheet features a finely woven 180 thread count, 60% cotton/40% polyester blend in a single-pick construction that delivers a tight-weave for long-lasting durability..