These are the beer mugs that keep beer chilled between 32° F and 36° F for 30 minutes. The double-walled mugs have a viscous cooling liquid between both layers that freezes after one hour in a freezer, enabling the mugs to chill a room-temperature libation to 36° F in just 2 1/2 minutes. The mugs are made from durable, hand-blown borosilicate glass, they each hold 14 ounces, and their shapes reveal the color and carbonation of beer while maintaining a broad, foamy head. Hand wash. Set of Four. 5 3/4" H x 3 1/2" Diam. (15 1/2 oz.)