A29 Moscow Mule 100 % Solid Pure Copper Mug /Cup, Set of 4 (12-Ounce, Patina Finish) 100 % Solid copper construction with beautiful ever lasting Classic Patina finish. No inner lining. Externally lacquered to prevent tarnishing. Great for moscow mules, beer and other cold beverages as well Capacity 12 oz Frequently used both at homes and at bars. Preferred by Mixologists !