Material】Aquarium air pump control valve is made of high quality ABS material, sturdy, and long service life.Package Included: 20 x Aquarium Control Valve 【Suitable For】Suitable for aquarium standard air line tubing and CO2 tubing with inner diameter about 4 mm. 【Application】Two-way plastic valve can be used as an embedded valve to control air from pump. Help to increase oxygen and keep air fresh, create healthy environment for your fish. 【Easy installation】Easy to connect hose, just insert the connector directly into the air pipe. convenient to operate and use. 【Quality Guarantee】Customer satisfaction is very important to us, if you have any dissatisfaction on the quality of goods, please contact us, we are willing to send you a new goods or a full refund.