... Underground water detector 1.With the variation of apparent resistivity 2.Micro-PC controlled,resistivity value read QJ-8 Underground ... it is widely used for searching underground water and non-metal ores (quartz mine, calcite mine ... includes hydrology, environment, engineering prospecting, metal and non-metal mineral source detect etc.Specifications:External HT ... °C~+50°C QJ-8 Underground water detector