A few years ago, battery powered soldering irons used to be about as much use as an ashtray on a motorcycle. Things have changed and while 6W won't be enough to solder the Titanic back together, it's plenty for on-site repairs and PCB work and heats to soldering temperature in about 10 seconds. It also has a safety cover that prevents damage to the tip and prevents the power being turned on when it's in the drawer of a toolbox. Requires 3 x AA batteries.