Double Wall 18/8 Stainless Steel Copper Vacuum Insulated Thermal Tumbler 20 oz. - Brushed Stainless 20oz. Double Wall 18/8 Stainless Steel Copper Vacuum Insulated Thermal Tumbler. Copper plated interior inner wall prevents heat from entering the double walls by thermal radiation. Enjoy up to 8 hrs Hot or 16 hrs Cold use. All Metal Body Construction from High Quality Materials, with Excellent Fit & Finish. Brushed Stainless Exterior Finish, Stainless Inner Liner, with Copper Coating In-Between. With a Simple Slide of the Swivel Tab, the lid is ready to Seal, Sip, or Straw from. Clear Acrylic Lid with Silicon Seal Locks securely in place to prevent spillage. BPA Free. Dimensions: 2.75" base diameter, 3.25" fill mouth opening, 7" height with lid Hand Wash Recommended, due to Individual Dishwasher Temperature and Abrasiveness Variations that may cause damage to the exterior paint finish and plastic components of the tumbler.