Emits 4,000 or 9,000 BTU/hr radiant heat Designed and approved for indoor and outdoor use Heats up to approximately 225 square feet Features emergency low oxygen safety system 2 temperature settings: low and high Runs 5.4 hours on low and 2.4 hours on high with 1 lb propane cylinder Constructed with self-extinguishing materials The use of un-authorized accessories/attachments with this heater are expressly prohibited, may cause serious injury, and will void the warranty.