It's a older model that isn't made any longer. That said, I remember them being made in the 70s and 80's maybe and seem to remember that they were pretty well built. Not sure how efficient it will be but it's a big piece of radiating metal, so it ought to heat well. They had an advertising campaign where they threw a stick of TNT into the stove and closed the door Don't try this at home!
I read that TNT story in an old advertisement. This stove was built in 78 but look almost new. I figured the same with that much mass its bound to heat well. My current stove was built in a dumpster fab shop and is little more than a metal box with a hole in the top lined with fire brick. been serving up well for 7yrs now but this came available from a neighbor and thought it looked like an upgrade.