Old 1930s or 1940s vintage, very large American Beauty soldering iron, made by the American Electric Heater Co. in Detroit and marked with a US patent number from 1928. It's a model 3178, 300 watts and is about 7/8" across the base of the copper tip. It's about 16" long overall.
This soldering iron has some rust as shown and a very worn electrical cord. We've plugged this in and it gets hot, but you'll want to replace the cord as it's been patched in a couple places with old friction tape.