Set of 4 Moscow Mule Mugs, 16oz Size Copper-plated stainless steel (SS304) 16oz mule mugs Bare stainless steel on the inside surface to avoid liquid contact with copper Clean with detergent & warm water using soft sponge Do not put in dishwasher & do not use polishing cream (due to lacquer coating on outer surface) Great for cocktail parties at home or commercial bars & lounges