New from Mr. Heater is the HERO35: a 35,000 BTU CORDLESS propane powered forced air heater. Powered by propane and a 12v lead acid battery, this is the future of jobsite heat. Cut the cord for a full 8 hours on a single 5 hour charge. Equipped with Mr Heater Patented Quiet Burner Technology, this heater burns with 40% less noise, making the jobsite safer and enabling you to work with a little more peace and quiet.