Max sensitivity:R12,R22,R134a,6g/yr Ulitimate sensitivity:3g/ ... vocation of freeze, refrigeration, and air-conditioner2 The leak-detect for air-conditioner in the car3 It will respond ... . R12, R11, R500, R503 etc.HCFCS e.g. R22, R123, R124, R502 etcHFCS e.g. R134a, R404a. ... in fire-extinguishing system.Technical parameters:Power supply: 3VDC (2XAA battery) Max. Sensitivity: R12, R22, R134a are certified ...