Product use: rain rain sensor can be used for all kinds of weather monitoring and translated into output signals and AO. The sensor USES the high quality FR - 04 double material large area of 5.5 * 4.0 CM treatment of nickel plating and surface have fight oxidation electrical conductivity and life has more superior performance; The comparator output signal clean good waveform driving ability is strong for more than 15 ma; With potentiometer sensitivity adjustment The working voltage of 3.3 V to 5 V The output format: digital switch output (0 and 1) and analog AO voltage output; Has a fixed bolt hole convenient installation Small board PCB size: 3.2 cm x 1.5 cm The LM393 use of wide voltage comparator Note: the line's color may be different from picture show but we sure function is same.