Precise adjustment: This CO2 controller is equipped with two instrument indicators and clean, accurate dials (0-80 psi output / 0-3500 psi tank pressure) for real-time monitoring and setting, ensuring optimal carbonization control for beer machines and home brewing. Easy to use: Efficiently hold the CO2 pressure by turning the knob. Before use, put the middle pressure control wheel to the loosest position, after all connections are made, open the bottle button, wait for the high pressure indicat