Tone and Probe Kit, Xpert - 

The 811K-G from Greenlee Communications is a digital high performance tracing kit. This kit combines 77GX tone generator and 200XP probe in a rugged carrying case. It is a wire and pair tracing tool that is both universally compatible and virtually noise immune. Whether tracking wires in a clear and quiet location or trying to find a wire in an area roaring with power hum and digital crosstalk, the 200XP probe and 77GX tone generator work efficiently. The tracing pair is also capable of working with any older type conventional tone probes and tone generators high noise immunity. It provides adjustable to a wide range of applications, flexible connection, ID577™ compatible and universally compatible with older equipment. The 200XP has probe tip resistance of 300 ohms minimum, 30dB filter 2 out-of-band rejection, 100Mohm input impedance and 35decibels gain. The 77GX has output voltage (talk battery into 600 ohm) of 5.5VDC.