The Ground Level’s Standard Cot Sheets are made of High Quality 50% Cotton 50% Polyester fabric. We use 1.5″ binding sewn all the way around the sheet, not surged. Heavy duty 1/2″ braided elastic (not knitted) on all 4 corners of the sheet. Our elastic is sewn into the binding to secure the elastic, then we add 8 bar tacked stitches to each end of the sewn in elastic, to give the sheets years of durable service. Made in the USA.