Simply add liquid to activate the flashing multicolored LEDs in the cup's base. As an added convenience, the lights automatically turn off when the cups are empty. Once activated, the LEDs create a mesmerizing display as they flicker, change color, and glow in a beautiful changing rhythm. This captivating light show is sure to delight and add a touch of magic to any occasion. Experience the joy of sipping your favorite beverage while being enchanted by the enchanting lights dancing in your cup. Add a touch of magic to your celebrations with our versatile drinkware party favors and decorations. Perfect for Christmas, New Year's Eve, birthdays, weddings, shots, bars, nightclubs, or discos. Our LED light-up cups create a mesmerizing experience with liquid-activated colorful LED lights that add a vibrant and festive atmosphere to any party. The lights automatically change colors, enhancing the ambiance and creating a beautiful rhythm. Introducing our sophisticated angular design Old Fashioned Lowball glass, featuring mesmerizing blinking LEDs that will leave your guests and friends in awe. Elevate your drink experience and make a lasting impression with this unique and unforgettable piece. Our Old Fashioned Lowball glasses comes equipped with two long-lasting 2025 coin lithium batteries, ensuring hours of uninterrupted LED light display. These batteries are conveniently included and pre-installed in the bottom of the cup, ready to illuminate your celebrations. To provide added durability and protection, the battery compartment is securely sealed with a twist-on liquid-resistant cap. Material: PS Dimensions: 8.5cm diameter, 9cm height, 8cm bottom diameter, Product capacity: 280ml, Light colors: red, yellow, green, and blue. Two built-in CR2025 button batteries are replaceable. Attention: It is not suitable to pour boiling water above 60 degrees directly into it