These silicone bands are for sealing food bags and bundling tools. They can be used from boiling water to the freezer. Specifications/Materials Body: Silicone rubber Heat resistance: 150_°C Cold resistance: -20_°C Dishwasher safe. Freezer safe. Depending on the period of use and the environment, a part of the silicone rubber material may separate, and a white powder may appear on the surface, but this does not affect safety or functionality. [About Shipping] Shipping will be done within 24 hours of purchase. In principle, anonymous shipping will be used. [To those considering a purchase] We are very sorry, but we ask for no claims and no returns.