A/C comp control?

[71C10Guy]

So I have had a manual switch inside my 71 4 seasons for a year now to control my compressor. I found out today there is what looks like a potentiometer off of a stove or something under the dash that will kick the compressor on or off. It does have a line coming off of it that senses temperature to control when the compressor kicks on, but I can't believe this is what came stock on the c10, unless there used to be a gear on the knob and the hot / cold slider moved it? If this is stock, what is the part called? Thanks!

Some pictures: https://imgur.com/a/9ZnSj3M

PS: sorry for potato quality pictures, phone is broken so using potato.