Gosh, that looks like it’s from the ‘50s or ‘60s. How does it work?
When you push the handle back, the silver looking piece with all the slits in it raises up. Underneath it is a plate that you put the meat on.
When you pull the handle toward you, the slitted piece goes down pressing against the meat and the blades roll thru the slits almost cutting thru the meat.
You then push the handle back and the plate the meat is on rotates 90 degrees, So when you pull the handle toward you the meat is sliced again at 90 degrees to the first cuts.
It sure helps me make chicken fried venison.