Stainless Steel Outer and Inner. Double Wall Construction For Insulation Of Hot Or Cold Liquids. Vacuum Insulated. Perfect For Keeping Your Favorite Wine Colder For Hours. Screw On, Spill-Resistant Lid. Wide Mouth Opening. Keeps Drinks Cold Up To 24 Hours and Hot Up to 12 Hours. Meets FDA Requirements. BPA Free. Hand Wash Recommended.