Also known as Growlers, these Swing Top Bail Wire Glass Bottles are very stylish. Bail wire is constructed of heavy-duty, zinc-plated steel wire. Stopper is constructed of solid plastic with a food-safe rubber seal. No need for caps or a capper with these flip cap bottles. Re-usable gasket /cap assembly snaps firmly into position by means of a wire cam. Great for not only beer but also home made syrups and sauces.