General description The 4/6mm Stainless Steel One Way Check Valves are designed to prevent backflow of water in aquarium systems, ensuring the proper function and longevity of CO2 cylinders. These valves are essential for maintaining a stable environment in aquariums and fish tanks. Technical specifications Material: Stainless Steel Size: 4/6mm Compatibility and accessories For use with steel CO2 pressure vessels only Not compatible with oxygen pumps or DIY equipment Installation Easy to install without additional tools Can be positioned anywhere in seconds Usage Prevents backflow of water caused by aquarium drawdown Protects motor head from backflow during power outages May prevent ozone from returning to the pump when used with ozone generators