Most fan controllers are just a switch: the engine gets too hot, the fan slams on at full speed, and it stays there until the coolant overshoots the other way. That costs an amperage spike every cycle and makes a lot of noise. This one varies fan speed instead, running the fan only as fast as it needs to hold the temperature you set.

Proform 69596 Digital Variable-Speed Electric Fan Controller Features:

• Runs a single fan or two fans at the speed needed to hold a set temperature.
• Adjustable between 150 and 240 degrees F.
• Substantially reduces electrical amperage spikes compared with an on/off controller.
• Engages the fans gradually to cut noise and fan wear.
• Bright digital display readable in Fahrenheit or Celsius.
• Weather and temperature resistant billet aluminum housing for under-hood mounting.
• Both a push-in radiator fin probe and a thread-in brass probe included.
• Relay, wiring harness, hardware and terminals included.
• Works with most 12-volt brushed motor fans.
• Sold as a kit.