These are the chilled beer glasses that keeps a draft ice cold without leaving unsightly rings on furniture. Simply freezing each glass for four hours activates the thermal liquid within its double walls, turning the crystal-clear glass frosty white. The glass quickly chills a beverage and keeps it cold for up to an hour without diluting it as melting ice does. The removable natural cork sleeve serves as a built-in coaster that prevents rings from forming on tabletops, and provides a comfortable, insulated grip for your hand. Can also be used to chill iced tea, lemonade, and soft drinks. Made from shatter-resistant borosilicate, the mouth-blown 15 1/2 oz. glass is dishwasher safe; cork sleeve washes by hand. 6 3/4" H x 3 1/4" diam. (1 lb.) Set of two.