This next-generation refrigerant leak detector uses an innovative infrared absorption sensing cell that is extremely sensitive to all refrigerants-and only refrigerants.Sensitive To All Refrigerants, Including R-22, R-134A, R-404A, R-410A, R-507 (AZ-50) And All CFCS, HCFCS And HFCS 1,000-hour infrared cell life for low cost of ownership Manual zeroing ignores user-programmed refrigerant levels when activated Infrared cell does not weaken over time, so response remains consistent and accurate Infrared cell cannot be overloaded or "poisoned" by exposure to large amounts of refrigerant High-efficiency air sampling pump provides quick response and quick clearing ("zeroing")on-board diagnostics indicate charging status and warn of low battery or infrared cell failure Nimh battery is environmentally friendly, won't corrode, and provides greater charging capacity enhanced filter design for superior filtration and resistance to contaminants Ability to run off ac power adapter Made in the usa