Allows the capillary sensor to be fitted in place of the standard electrical transmitter.
Fits neatly into the top radiator hose and you can also adjust the temperature.
This thermal switch also comes with the Aluminium Radiator as there is a pre-drilled boss in it. It can also be fitted to other radiators but be prepared to remove your radiator and have a 22mm boss welded in at a radiator shop.