Specialist measures show! It continuously measures up to 24 hours on 2 MW boilers, engines, turbines ... Approved for regulators, it scans up to 8 gas. IN Version: O2, CO comp. H2, with carrying case - up to 6 electrochemical cells. INS version for corrosive gases inside TEFLON and Peltier cooler in stainless steel - up to 6 electrochemical cells (including H2S, HCl, NH3) and up to 3 physical quantities measured via a sensor type NDIR (Non-dispersive infrared)