Northwave evolution shoe coverthe evolution is a performance shoe cover ideal for use in time trials or similar disciplines the lightweight fabric has been given a dwr durable water repellent finish to make it more water repellent the inside of the shoe cover is black to disguise dirt from the crank for a tighter more aero fit an internal silicone band on the ankle keeps the shoe cover in place additional silicone grips at the inner ankle keep the cover in contact with your shoe at all