The Hydro Flask 18oz Wide Mouth Insulated Bottle is a stainlesssteel bottle for transporting your favorite drink from place toplace. The 18/8 pro grade stainless steel is not just BPA-Free, butincredibly durable so as not to bruise your water. The bottle isinsulated, allowing cold drinks to stay cold (up to 24 hours) andhot drinks to stay hot (up to 6 hours). Because nobody wants a hotwater or a cold coffee. Shoot, unless you like iced coffee.