Fine bubbles,The cell board produces bubbles finely. Beautiful bubbles will also make oxygen supplements vigorously. It helps to increase oxygen, maintain fresh air and create a healthy environment for fish. Silent design,The aerobic bubbling oxygen stone is a silent design. With the pump as the driving force, the power of the gas lift is fully utilized, and there is no power device itself, and there is no noise during work. Even if you sleep, it will not affect. Adjustable,The bubble stone has a rotatable design. The size and density of the bubbles can be arbitrarily adjusted. Add a different effect to your fish tank. Suction cup designThe superior suction cup design is used to fix the air stone to prevent friction and wear and prolong its service life. Suitable for different occasionsAquarium oxygenated bubble stones can add air flow,circulation to your aquarium, pond, hydroponics and aquaculture to oxygenate water and benefit aquatic life. Specification: Material: Plastic Color: Black Height: Approx. 5.3cm / 2.1 inch Package list:1*Air refiner Note: 1. Please allow a little error due to manual measurement. Please make sure you don't mind before praying< br> 2. The color may vary depending on the display. Please understand< br> Note: Hello, please pay attention to your shipping address when purchasing products. If your receiving information (such as name, street, house number, doorbell/email without name) is incorrect, the order will not be delivered correctly.)