ac infinity 4inch fan , controller 67 for exhaust , 78* target setting lights on . lights off low temp of 62* , hits the low target it turns on to high speed to help suck in warmer air quicker. lights off i've got a generic no-name 6 inch intake fan piped to in front of a house heating vent .inkbird controller set to come on at 64* . maintains my temps to around 80-82 lights on and 65-67 lights out. ezee pezee lol