This Travel Tumbler Features Stainless Steel Metal Outer & Inner Walls & is Copper-lined. It is Double-wall Vacuum Thermal Insulated & Keeps Your Drink Hot or Cold for Hours (keeps Cold Up to 18 Hours & Keeps Hot More Than 8 Hours). Sweat-resistant, Bpa Free & Includes a Spill-resistant Slide Lid with Rubber Gasket. Ships Assembled. Hand Wash Recommended.