A total utility locating kit in one: includes the SeekTech SR-20 Locator, ST-305 Line Transmitter and Inductive Signal Clamp. This lightweight yet rugged system delivers the information you need to locate buried utility lines. The SR-20's omnidirectional antenna system measures electromagnetic signals and calculates the signal’s orientation strength, depth, and degree of distortion or interference, so you can work through difficult locations. The large display and the multidimensional audio cues help with training.