DEO-FRESH - BLUE: Keeps your feet and shoes fresh. Go sockless! if you want to because Deo-Fresh-BLUE is hand washable. Deo-Fresh-BLUE is made of pure, soft, cotton terry and durable, natural sisal fibers that are safe for prolonged contact with bare skin. Sisal has been used for centuries to make rope on ships. Better still Deo-Fresh-BLUE incorporates nano sized silver ions to permanently prevent the growth of bacteria. This makes Deo-Fresh-BLUE ideal for boating, cruising, warm weather travel, tennis, walking-you name it. With Deo-Fresh-BLUE your feet and shoes stay cool, odor resistant and comfortable.