This multi-purpose wire tracer features both audible and visual indication of any non-energized wires such as coax, CAT 5, speaker, etc. Adjustable sensitivity allows you to identify a single wire when multiple wires are routed together. Auto-off function. Uses 2 AAA batteries in the transmitter and 4 LR44 batteries in the receiver. Includes adapters for RJ-45, RJ-11, coax, blade fuses, and insulated clamps.