Representing the top 1% of cotton in the world, Supima® Cotton is premium, 100% American grown. Incredibly robust, soft, and breathable, it is extra-long, staple, cotton. Malouf's Supima® Cotton Sheets, have a 600 thread count and feature a luxurious sateen weave. Double the length of regular cotton, Supima® resists breakage, as well as pilling or tearing. These remarkable sheets are breathable, pill-resistant, and are mercerized for softer, more vibrant color. The Universal Fit™ design utilizes ultra-thick elastic, and extra-deep pockets, ensuring a secure fit for mattresses from 6" in profile height, up to 22". Sets include 1 fitted sheet, 1 flat sheet, and 2 pillowcases. The King split set includes 2 Twin XL fitted sheets, one King flat and 2 pillow cases. Please note, consists of a single pillowcase for twin and twin XL size.