This product CANNOT be purchased with Financial Aid/Student Account. The straw lid fits the 12 oz., 16 oz., 18 oz., 32 oz., 40 oz. and 64 oz. wide mouth Hydro Flasks. Like all Hydro Flask products, the straw lid is both bpa and toxin free. The Hydro Flask straw lid is an easy to use flip straw designed with a high-flow rate and a durable rubber coating to withstand bite marks.