The analogue Martindale Fuse Finder Kit (FD500) finds which fuse or breaker controls a circuit. It also enables tracing from socket to socket on a circuit. The transmitter (FD500/T) takes its power from the mains and emits a signal which the adjustable sensitivity receiver (FD500/R) can pick up. This combination can easily distinguish the appropriate circuit, even on a crowded fuse board. Sensitive analogue adjustment by thumb wheel finds the right breaker rapidly. The FD500 fuse finder kit is supplied with a transmitter, receiver, batteries and instruction manual.Easy location of fuses and breakersSimple thumb wheel adjustment of sensitivityFor use on live circuitsSocket to socket tracingAudible and visual indication