The original factory radiators of the late 80s and 90s had a clip and seal to hold the fan switch in.  Those tended to fail by popping out of place at the worst time!  Our special aluminum radiator, and  some of the 2 core 'Supercool' and 4 core radiators use this screw in type switch for extra safety. This is the replacement switch if your radiator has a threaded hole or a "drain plug" that is about an inch in diameter.  Kicks the fan ON at 197F (92c) and off at 179F (82c).

Fits the following radiators:

- Super 2-core Radiator C-ARA4443
- 2-Core Alloy Side Mount Radiator C-ARA5000