Getting heat to where it’s needed on a wintry job site may be easier with the Hero cordless forced-air propane heater. Its maker says that this compact 12-pound unit delivers 35,000 Btu of heat — enough to warm 800 square feet. It can run for up to 12 hours on a 20-pound tank of propane and make it through a full day’s work on a single battery charge, the company says. It’s also quieter than other forced-air heaters and comes with an integrated charger that revives a dead battery in 5-1/2 hours. It costs about $190. Mr. Heater, 800/251-0001,