Our Refurbished Digitrak® ST Green transmitter is compatible with the DigiTrak SE® locator used for horizontal directional drilling. The sonde features extended-range capability, pitch readings in 1%, and depth up to 50 ft. Specification:Compatible LocatorsDigiTrak SE®Pitch1%Depth50ftFrequency12kHzBatteries2x C-cell Alkaline 1x SupercellLength15.0 inchWidth1.25 inch