Narrow Twin Size Cot Sheet 31″ x 75″ x 9″ – 3 Piece Cot Sheet Set – RV Bunk/Camp Bunk/Guest Beds/Army Cots/Trifold Mattress, Dark Grey Solid. Ultimate Sleep Support: The sheets are designed to provide ultimate sleep support by being super soft, breathable, and skin-friendly, akin to the feeling of a T-shirt against the skin.