The Mr. Heater Tag-A-Long 8,000 BTU Portable Radiant Heater has 2 heat settings to deliver 4,500 - 8,000 BTU of heat for a space up to 200 sq. ft. Safety features include a tip-over switch that shuts-off the heater if it gets knocked over and a low-oxygen sensor that shuts the heater off when oxygen levels in the room get too low. The heater also will shut-off if the pilot light goes out. It will run for up to 4-1/2 hours on a 1 lb. cylinder and up to 96 hours on a 20 lb. tank. The heater can be free-standing or wall mounted. It is clean burning, CSA approved and nearly 100% efficient.