Antique Copper Hammered Hard Moscow Mule Mug Set Of 4 The mug keeps the drink colder longer without needing as much ice but also because the acidic lime juice tastes a lot more sharp and crisp against the metal cup compared to a traditional pint glass. Glass just doesnt feel as cold copper and it doesnt make the lime bite as much either. The most scientific benefit of using copper moscow mule mugs is temperature. For centuries, the best drinkers have known that chilled drinks in copper cups offer an extra-cool sensation, due to the metal quickly taking on the icy temperature of the cocktail. Simply put this old-timey cocktail just tastes better (and feels better) when it is served directly out of a copper cup. Hammered Solid copper body with brass handle Set Of 4 Antique Finish Copper Mug