You have to be careful with that type of controller. I use three bulbs in my brooder (it is in a cold space and I brood a lot of birds (50)). Only one of the bulbs is controlled by the unit. Here are the snags that I found with the unit (with the inkbird I use):
1) The temp set point. The unit is on until the point is exceeded, so if you set it to 95 it will heat until it is 96. At that point, the temp will continue to climb until about 100.
2) On the cooling cycle it has to get 1 degree lower than the temp, my ceramic bulbs take a bit of time to get going. So they cool off about five extra degrees before they start heating up.
So I couldn't have all the heat bulbs doing this at the same time, it was like watching the ocean waves while the chicks ebbed and flowed. By leaving two on and having them at the right height, the third controlled bulb handles the change needed as the temp outside drops.