The 811k/6A Digital High Performance Tracing Kit 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 77GX2 tone generator work efficiently. The tracing pair is also capable of working with any older type conventional tone probes and tone generators.