Specifications: Material: Stainless Steel Color: As the picture shown Size: 408mm The pneumatic check valve can prevent the aquarium from backflowing water, which is caused by the decrease, and keep the function and service life of the carbon dioxide bottle.NOTICE: Only used for containers under carbon dioxide steel pressure and cannot be used for DIY and oxygen pumps because the pressure is not enough to operate the valves. When used in the generator ozone, the air check valve can prevent the ozone from flowing back to the air pump and eroding the propeller. The aquarium check valve can protect the supply head from water backflow caused by power outage. The simple check valve is easy to install, requires no additional tools, and can be attached to any location in your home. your choice in a few seconds condes. These stainless steel one-way check valves are suitable for CO2 supply system in aquariums, aquarium and the like.