Aquarium Fish Tank 2 Gauge CO2 Pressure Regulator Bubble Counter Solenoid Valve*
1x 220V Aquarium CO2 Regulator W21.8. Cryogenic solenoid valve, with corrosion resistance, longer service life. The Cylinder Pressure Gauge: The bottle pressure would change as room temperature, It is normal if it shows between 500 and 1000.