Bound With Cotton String.Our attractive bamboo Sushi Mats are imported from Japan where they are used daily as a versatile kitchen tool. They are made from superior quality, thick, untreated bamboo strips bound together with thick unwaxed cotton string to make a flat, flexible surface. Ours is considerably more versatile and durable than those made with thin strips of bamboo.Traditionally called "sudare" or "maki-su" that mean to roll.Recent studies of cooked food, exposed to long term wrapping in plastic, showed chemical absorption, especially in warm foods. Our Sushi Mat allows food to breathe without condensation that detracts from the flavor and promotes spoilage.They are easy to wash and easy to use. Once you try them, you may want two or three.