All instruments in the Target Range come complete with sensors or transducers as appropriate and all necessary fittings. They are designed to run on 12v supply but due to the very low power consumption there is no reason why they cannot run off dry batteries. They provides accurate readings for owners of sailing craft and powerboats alike. Following the NASA design philosophy the Target Log is simple and reliable showing speed in knots trip distance to 999 nautical miles and total distance run up to 999 nautical miles.