Direct Info from Product Website : https://www.co2art.eu/products/new-co2art-pro-series-precision-co2-check-valve

High-pressure +100psi resistance CO2 check valve. With the incredibly low opening cracking pressure of 1 psi !

Permits flow of CO2 in one direction only, protecting your system from water backflow and solenoid damage.

Easy push-in connectors allow easy inline installation.

Compatible with all CO2Art CO2 resistant tubing types.