This Hydro Flask Straw Lid is for wide mouth Hydro Flasks and features an easy to use flip straw which is specially designed with a high flow rate. It is made of durable polypropylene and has durable rubber coating to withstand bite marks. It is compatible with all newer styles of wide mouth bottles. The convenient finger loop helps you clip your bottle on the go. It is BPA-free and has Lifetime Warranty.