Patent numbers...I just found some text at the Base of the blade, I think it says something like patnos
Imperial frequently put Pat Nos on the blade. That knife is an Imperial Hammer Brand bowling pin knife. Its a shell construction knife, the handles are thin sheets of celuloid wrapped over the steel shell handle.
Not worth restoring IMO, just a cheap novelty item from the 50s and 60s.
This knife has been sitting in a drawer for a few decades and is in pretty poor condition. I don’t know the manufacturer and I’m curious to see if I can get a replacement or if I will have to get it restored.