Reading the temperature gauge

Thanks for the replies so far. I was afraid that would be the answers I would get. I'm installing electric fans and using the Pac 2750 as the fan controller. I'm trying to map the controller to my temperature sender by programming temperatures in based on the tick marks on the standard gauge. Assuming the standard gauge is operating correctly, I assume the marks represent some predetermined temperature. I may have to use the temperature selection on my Fluke to verify and calibrate the controller.

Trailbeast that's how it usually goes.