Cafurty Air Bubble Increaser for Aquarium Fish Tank Adjustable Oxygen Increase Ball Air Pump Accessory Aquarium Appliance Package List: 1 * Air Increase Ball with a Sucker. Air Bubble Ball / Sucker Color: Blue ; Material: Plastic Diameter of the Air Bubble Ball: 1.7cm / 0.67in ; Sucker Diameter: 2.7cm / 1.06in Have a sucker, thus it can be set at any place of the tank. It can make numberous bubbles to create a fantastic scene.