Features:_x000D_This air stone needs standard size air hose and air pump to run it, it can39;t produce bubbles in water by itself. Please note that NO air hose and air pump are included in this kit._x000D_Ultra-high dissolved oxygen:This high-quality aquarium air stone releases bubbles more smaller, denser, uniform, which makes double oxygen dissolving rate in water, the more air goes into the water, the fish pets can live a more happy life in the aquarium tank_x000D_Small and dense bubbles:The air aquarium stone produce smaller and denser smooth bubbles than general air discs, when the bubbles burst into the water, it39;s ultra quiet under water. It can creat the atomization effect, the bubble beams will make your aquarium like a fairyland_x000D_Weighs enough to sink: The air bubbler stone easily sits on the tank bottom without suction cup. Suitable for freshwater and saltwater_x000D_Super sturdy anddurable, easy to clean,strong filtration._x000D_Specification:_x000D_Size:_x000D_S:Diameter:10cm_x000D_M:Diameter:13cm_x000D_Thickness: 2cm_x000D_Scope of application: applicable diameter is 4mm8mm inner diameter hosePackage List:_x000D_1x Aquarium Air Stone