Small, gold colour face motormeter (temperature meter) to fit in to radiator cap, 60mm approx diameter. requires 11mm hole in cap for fitting. the temperature sender bulb is approx 38mm long. It is not essential for this to be immersed in the water, as it will still function via the warmed air above the radiator coolant.
Please note that the glass thermometer is angled for best sight from the left hand side of vehicle.