Widely applied in Checking Short Circuit, Locating Open Circuit, Wire Tracing, Wire Identification etc. Quickly and easily target broken wires, current leaks and so on | Diagnose and judge the break point from Slight Change of the continuous audio signal from receiver. Transmitter and receiver LEDs show open or short circuit conditions | Operates on DC voltages from 6 to 42 Volts under any circumstances | 7" flexible Probe allows reaching wires in congested places; Adjustable sensitivity for all tracing needed. Internally protected against power surges and overloads | Delicate bag included, easy for carring and storage. Powered by 2 pieces 9V 6F22 Batteries (NOT Provided by Seller) | Fit type: Universal Fit