The sender unit is the in-tank component responsible for transmitting fuel level readings to the dashboard gauge on the Series 3 109-inch Station Wagon. It consists of a float arm and resistor track that varies electrical resistance as the fuel level changes; a faulty unit typically causes an inaccurate, erratic, or fixed gauge reading. Correct replacement with the specified unit ensures the gauge reads accurately across the full range from empty to full. Key Features Designed to the original resistance specification for the Series 3 109-inch Station Wagon fuel tank configuration Direct replacement requiring no modification to existing wiring or tank fittings Matches OEM fitment for vehicles up to Suffix B, where tank and sender specifications differ from later production When replacing the sender unit, inspect the fuel tank sealing gasket and float arm for corrosion or deformation before refitting Vehicle Fitment This sender unit fits the Land Rover Series 3 109-inch Station Wagon only, covering vehicles produced up to Suffix B. Not sure about fitment? Feel free to get in touch at [email protected]