If you have a variable speed blower motor get one of these ECM savers. It is inevitable that a voltage spike will take out the ECM portion of your blower motor & most HVAC repair company's will not repair or replace just the ECM unit they want to replace the whole blower assembly (which I recieved multiple quotes right around $1500 to replace the whole motor assembly). The issue is mosqt HVAC suppliers are whole sale only & will not sell to the public. I fixed my ECM unit for $27 & then purchased this ECM saver to further protect from future issues. This ECM Saver fit my GE ECM 2.3 motor. Completely worth every penny for the added extra security!