Oxygen percent of delivered gas, flow rate in LPM, output pressure in PSIG or kPa. A small hand-held unit, which delivers all three essential validation checks required to assure proper oxygen concentrator performance. There's no need to carry a tool box full of test equipment to measure concentrator performance or spot check LOX systems anymore. With microprocessor logic and ultrasound technology?and one simple tubing connection?you'll be ready to go! It comes complete with a carrying case and a 9-volt pre-installed battery.