Maxxair 00-965001 Turbo/Maxx 3 Speed Fan with Thermostat Power 12 volt, 4 amp motor provides over 900 CFM on high speed, 680 on medium and 500 on low at 1.4 amps. Large 12 inch diameter opening with 10 bladed fan allows high volume air flow Roof mounted motor and fan blade provide quieter operation