The Rumi Lota bottle is insulated. It keeps contents hot for up to 12 hours and cold for up to 24 hours. The body of the bottle is sustainably made with stainless steel to reduce the wasteful use of plastic in carrying drinks. The bottle is easy to clean and meant only for hand washing. The sustainable materials used to make the bottle are food-grade BPA-free and odor-free.Made of kitchen grade stainless steel. It is highly durable and easy to clean.