REFURBISHED—We know you need your equipment to work as hard as you do. Trust MASTER’s Propane Forced Air Torpedo Heater to get the job done. It will warm up to 1500 square feet of your shop, barn, construction site, or wherever you need powerful, dependable heat. This high-output heater’s time-tested design includes the built-in convenience and advanced safety features you expect from MASTER products. MASTER – built for power. Operates on clean-burning propane.