Mr. Heater F232017 MH9BXRV Buddy Grey Indoor-Safe Portable RV Radiant Heater (4,000-9,000-BTU) 4,000- to 9,000-BTU radiant heater for spaces up to 225 square feet. Approved for indoor/outdoor use; clean-burning; nearly 100-percent efficient When operating the heater at altitudes over 7,000 FT above sea level the heater may shut off. Auto shut-off if tipped over, if pilot light goes out, or if detects low oxygen levels Fold-down handle; swivel-out regulator; connects to propane tank (not included).Fuel Type:Propane THE USE OF UN-AUTHORIZED ACCESSORIES/ATTACHMENTS WITH THIS HEATER ARE EXPRESSLY PROHIBITED, MAY CAUSE SERIOUS INJURY, AND WILL VOID THE WARRANTY.