This 12-oz. double wall 18/8 stainless steel thermal mug with copper vacuum insulation, stainless steel rim, clear push-on lid, swivel closure, and powder coated finish; Hand wash recommended; Do not microwave; 4" h x 4-3/4 w (with handle); 355mL;. Keeps beverage hot for 8 hours, and cold for 16 hours.