Features: 1.Anti Clogging: Aquarium air stone with high density pore, refining bubble stone, bubble is dense, long use without clogging. 2.Sturdy And Durable: Fish tank air stone is fixed with metal material, not easy to damage, long time resistant to use. 3.Increase Dissolved Oxygen: The use of bubble stone can improve the water dissolved oxygen, to meet the problem of oxygen deficiency. 4.Application: Tower type air tube interface, adaptable to 4mm/0.16 air tube standard interface, tight connection is not easy to fall off. 5.Widely Used: Aquarium bubble diffuser stone is suitable for all kinds of fish tanks and fish pond, a practical oxygen pump accessory. Specification: Item Type: Aquarium Air Stone_x000D_ Material: Air Bubble Stone, Metal_x000D_ Size: Approx. 18 x 41 x 6mm / 0.71 x 1.61 x 0.24in_x000D_ Use: Fish Tank Oxygen Pump Bubble Stone PackageList: 1 xAquarium Air Stone Note Manual measurement, please allow some errors.