This cup is environmental protection transparent shine cup, when pour into liquid (water, juice, beverage, beer, etc), it will light up and flash immediately, very magical. Suitable for celebrate, party, bars, gifts and so on. Auto change led color after fill in water or beer. 3D dragon design around the cup, fashion and cool. Water activated: it glows automatically when drinks are added liquid, and it will turns off when there is no liquid left. Enjoy different drinking moment with this vivid mug. Type: LED Glowing Cup Material: Plastic Pattern: Dragon Power by: 2 x CR2025 Button Batteries(Included) Occasions: Pub, Club, Party, Cocktail, Halloween, Xmas, Wedding, etc Features: Eye Catching, Battery Replaceable, Color Changing, LED Flashing Diameter: 8cm/3.15", Height: 9.5cm/3.74" (Approx.) Notes: Due to the light and screen setting difference, the items color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 x LED Glowing Cup 2 x CR2025 Button Batteries