Two pressure gauges showing cylinder pressure and output operating pressure, easy to read setting High quality bubble counter allows you to see the amount of gas being injected into the tank by counting bubbles per minute, so you can adjust the bubble rate as you wish to create good growing conditions for your aquarium plants Adjust the high precision needle valve to control the amount of CO2 entering the aquarium, ideal for use in planted aquariums or other applications that require precise CO2 control Each kit includes regulator, bubble counter, solenoid valve, wrench and O-ring. Industry standard nut, compliant with DIN 477 / BS 341 No. 8 / W21.8-14 (covers UK and Europe) It takes a few minutes to release the trapped gas when the solenoid is turned off. If you have any questions about this product, please feel free to contact us, we are always here to help you. Product Description Dual Gauge Pressure Indicators Dual gauges allow you to check the operating and cylinder pressure at the same time. Cylinder pressure gauge: 0~25 MPa / 0~3500 psi Outlet pressure gauge: 0~1 Mpa / 0~150 psi Fine adjustment The high-precision needle valve is quite sensitive, so only small movements are needed to change the CO2 rate, which can help you achieve the best regulation of the number of bubbles per minute. Easy installation The premium CO2 regulator comes with a wrench for easy installation. Connection: W21.8 Power supply: 12V 12V power supply included for safe and stable working. Read more Top tips: