Just add liquid to activate the LEDs on this shot glass. The lights turn off when the cups are empty. When activated, the LEDs flicker and glow. Best drinkware party favors or decoration for Christmas, New Year's Eve, birthdays, weddings, shots, bars, night clubs or discos. Height: 2.5". Top Diameter: 1.75". Bottom Diameter: 1.75" Ounces: 2