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This closure system converts standard—leaky—screw-top growlers into tight-sealing swing-top growlers. Made from FDA approved HDPE #2 – which can withstand high temperatures (120°C/248°F) for short periods – stainless steel, and food-grade rubber. They are dishwasher-safe, in the top rack. The closure system includes stopper, gasket, adapter and hardware. Does not include the bottle. Made in USA. Patent pending.