Feature:1. High strength, high temperature resistance, corrosion resistance, nontoxic and wearresistant.2. Ttype regulating valve, allows you to adjust the air flow freely in the fish tank.3. Help to increase oxygen and keep the air freshed, creating a healthy environment for your fish.4. Wide application, suitable for 4mm/0.2in hose, easy and fast to install.5. Sophisticated technology, accurate controlling, which is dependable to use.Specification:Condition: 100% Brand NewItem Type: Aquarium Air Volume ValveMaterial: Plastic Color: As picture shownFunction: Adjust the air volume of air pumpApplication: Suitable for 4mm/0.2in hoseInstructions for Use: Connect the regulating valve in the middle of the hose, and adjust the amount of gas by turning the blue valve.Package List:10 x Aquarium Air Volume Valves