Maxtec has improved the Handi O2 analyzer to better meet your needs for oxygen analysis. The simple to use, one-touch calibration button, new overmold and calibration reminder combined with the traditional 24 month warranty, auto-off and size make it the best of its class. The Handi+ will calibrate to room air (20.9%) or 100% oxygen. This product is great for spot-checking O2 percentage in various industrial applications. The Handi+ meets NFPA 99 requirement for an oxygen analyzer used to verify the effectiveness of a nitrogen purge.