... of leak gas concentration, easier for use, set range by manual is allowed. 5)Default or self-set alarm limit. 6 ... combustible sensor, thermal conductivity sensor, NDIR sensor (optional).Suction pump: diaphragm suction pump with the maximum flow of 1.2L/min, and the ... and dust-proof filter, cup probe, carrying case, User’s Manual in Chinese/EnglishOptional Accessories:Trolley probe, borehole probe