Liquid Activated Light-Up Flashing LED Drinking Cups Tumblers - Holds 7 Ounces, Batteries Included - Fancy Plastic Clear Crystal (4)Liquid Activated! Just add liquid to activate the flashing LEDs. The lights turn off when the cups are empty. When activated, the LEDs flicker, change color, and glow in a beautiful alternating sequence Great for parties, bars, nightclubs or discos! These cups are certain to impress and entertain! Made of durable acrylic plastic in a classy, old fashioned crystal design Batteries are included and replaceable Two CR2025 lithium batteries are pre