Mr. Heater Corporation Vent Free Radiant Propane Heater, 30k BTU 30,000 BTU per hour; For use with Propane Gas; Heats up to 750 sq. ft. Radiant heat burner Quiet integrated blower for gentle circulation of heated air Thermostat for automatic temperature control; Automatic low oxygen shut-off system (ODS) Blower fan kit (f299200 sold separately) - available for 20k units and up only