S'well bottles feature Therma-S’well® Technology with triple-layered, vacuum-insulated construction designed to keep beverages colder or hotter, longer than all the rest. Made from 18/8, foodgrade stainless steel. Offers a condensationfree exterior that won't sweat in your hands or bag. The 17oz emulates a standard size water bottle. Keeps beverages cold for 36 and hot for 18. Hand-wash only. BPA/BPS-free and reusable.