Instantly creating a mist of tiny bubbles that your fish will love, the Air Stone is the best partner of air pump and can evenly distribute fine bubbles in your tank. The bubble wall comes with a suction cup for convenient to attach it to your aquarium and a to control bubble amount. Features - Material: ceramic, ABS - Stone diameter: 50 mm - Overall diameter: 70 mm - Stone height: 26 mm - Air inlet height: 39 mm - Applicable tube inner diameter: 4 mm - Instantly create a great deal of tiny bubbles that your fish will love. - Come with a suction cup to produce enormous power to stick to glass surface firmly. - Please use it by connecting air tube with oxygen pump. And youd better soak it for two hours in the fish tank before use. - Warm Tip: Dear buyer, due to lighting effect, monitor's brightness, manual measurement and etc., there could be some slight differences in the color and size between the photo and the actual item. Sincerely hope that you can understand