Big heat right out of the box. The Mr. Heater 80,000 BTU Liquid Propane Convection heater packs a big punch in a small package. It utilizes the natural act of warm air rising to quickly heat up to 2,000 square feet. Equipped with a thermo-electric safety valve to shut the gas flow off if the flame ever goes out. The single knob is used to ignite the heater and control the heat from 30,000 to 80,000 BTU. Just hook-up the supplied 10ft propane hose and regulator assembly to a 20lb propane tank, then easily light the heater utilizing the factory installed Piezo igniter and enjoy the comforts of a toasty warm jobsite. It will run up to 14 hours on a 20 lb tank on low.