The Maxtec Handi" Hand Held Oxygen Analyzer, is everything it's always been and more! Maxtec has improved the Handi O2 analyzer to better meet your needs for oxygen analysis. The simple to use, one-touch calibration button, over molded case and calibration reminder, auto-off and size make it the best of its class. This analyzer is great for spot-checking O2 percentage in hospitals, clinics and in homecare environments. Handi Oxygen Analyzer, new affordable hand held analyzer that verifies oxygen content in your air and nitrox tanks. Simple to operate, affordable, maintenance free and has a two year battery life! Comes with an owner's manual and measures (H x L) 2.45" x 3.2" (6.22 cm x 8.13 cm).