This unit is brand new and was for a propane 40 gallon hot water heater. It was intended to fix my existing hot water heater, but the issue was the controller so it is no longer needed. It cost me $90 so I am willing to sell for $50. I will include the other pilot/ thermopile assembly from the old hot water heater that turned out not to be the problem in the first place. If you want the old hot water heater, you can have that too.