I'm sorry but i disagree with both of you. Go ahead spend $20 on a rheostat or Thermostat that only has 1 or 2 input outlets and then try attaching extensions to get more outlets. Or you can spend your money well, get a thermostat that has 6-8 input outlets and controls the temperature digitally by degree for $80. Seems like A LOT better idea buying something that is very easy to use and very quality with all the accuracy you would want. Call me skeptical, but when it comes to animals, really anything in life, you buy quality at first and you will never have to worry about it in the future.