AO Coolers Stainless Water Bottle with Copper Vacuum Insulation, 26-Ounce 26-oz double wall 18/8 stainless steel vacuum thermal bottle Threaded insulated lid to keep your drinks cold for up to 8 hours or warm up to 16 hours Slim enough to fit in standard cup holders Copper plated inner wall prevents heat from entering or exiting the bottle by thermal radiation