Stay away from this item, I bought it for my derale fan and it didn't even turn on when it should have turned on. I thought it was the wiring, make sure everything is connected properly. So I thought I had a faulty unit, they sent me a replacement from Revain (great customer service) and I tested the second unit in boiling water, it was supposed to turn on at 180, the water was at 200 and it still didn't work, talked to the guy in the auto zone about the temp sensors, he said the ones that come