There were a few different models of the Kingman hammer
The Hammer Model A had an aluminum grip frame.
The Hammer Model P had a plastic grip frame.
The Hammer Plus (not sure on the name) had a power feed.
The Hammer II was a sterling clone.
The Hammer III was an inline semi
I also had one that came with a box that had the same "New Hammer" marking, but other than the above differences, I don't know if they changed around the internals or anything, or if new was just one of the different versions.