Customized Tumblers & Travel Mugs, Basecamp K2 Tumbler - 30 oz - Vacuum Insulated & Copper Lined, 30 oz Vacuum insulated double wall tumbler with clear AS pressure lid. 18/8 powder coated stainless steel with copper lining; fits in standard cup holders. Not microwave safe; hand wash only. Packaged in retail box. Keeps drinks hot for 6 hours or cold for 12 hours!​ ... #BC8807 $15.34/each.