Its primary gauge delivers constant CO2 readouts, while a second gauge monitors remaining CO2 left in your cylinder ensuring you’ll never run out unexpectedly. The low pressure gauge mounted on top (12 o’clock position) reads from 0-60 PSI and displays the dispensing pressure (pressure in the keg), while the high pressure gauge on the left side (9 o’clock position) reads from 0-2000 PSI and registers the pressure remaining in the CO2 tank.