Our Refurbished Digitrak® DX Red transmitter is compatible with the DigiTrak MARK III®, MARK IV®, and MARK V® 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 MARK III, IV, V®Pitch1%Depth50ftFrequency33kHzBatteries2x C-cell Alkaline 1x SupercellLength15.0 inchWidth1.25 inch