Ceiling heaters mount to an electrical junction box installed in the ceiling (not included). These surface mounted ceiling heaters have a 20 gauge steel grill with white powder coat finish. Ceiling heaters feature an enclosed steel fin sheath element. Propeller fan blade is powered by a 1300 RPM motor, offering 425 CFM. Radial diffuser. 208V, 240V and 277V Heaters feature a manual reset thermal limit. 480V Heaters feature automatic reset thermal limits, 24V control transformer and a 24 volt relay. 1 Year Limited Warranty.