I have a CO2 regulator that measures psi from the tank, but "flow" to the out line in Liters/minute and cubic feet per hour. I think it is really for welding. But I have it now and don't want to spend more for one that shows psi. I looked online and there is no direct way to convert between pressure and flow; they are different things. Still once the tank, regulator and corny are hooked up gas flows into the keg until it reaches an equalizing pressure and then stops and holds that pressure. I'm guessing about the pressure on my beer. Anyone have one of these "flow" regulators? Is it usable? Any way to gauge the psi?