AQUARIUM CO2 CALCULATOR + CHECK VALVE R-120

Model No : R-120
CHECK VALVE + CO2 CALCULATOR AQUARIUM Product Description
Instructions:
1.Infuse water into this check valve

2. When used inside the tank, install the sucker and attach it to the tank wall. Connect the air-in hole with CO2 supply pipe; connect the air-out hole with CO2 diffuser.

3. When used outside the tank, apply the same method except the sucker part.