Avengersworld Handmade Pure Copper Moscow Mule Mug (Set of 4 Mugs) Made in Pure Copper. Capacity 16.90 oz per pc With Free 2 Small Copper Mug Shot High quality "hammer finish" Moscow Mule mugs with a solid Brass Handle. These mugs are constructed of 100% pure Copper. No plating, stainless steel or nickel linings. All copper construction makes for a quick frosting mug. Leave them in your freezer case. Hand Wash Recommended.