The RIDGID 5 Watt SeekTech ST-305 Line Transmitter lets you energize metallic lines for tracing and can transmit two frequencies simultaneously. Audio feedback confirms a good circuit before beginning a trace. Direct Connect : 1 kHz, 8 kHz, 33 kHz, 262 kHz.* Induction : 1 kHz, 8 kHz, 33 kHz, 262 kHz.* * Up to 93 kHz for devices sold in Europe.