That was one of the last saws out of "Disston Precision Incorporated" previously known as "R.A.F. Industries of Philadelphia".
Has nothing in common with a "real" Disston accept the name. In a few years it may become valuable if still in the box.
As far as a user goes, it's great! Tapered blade, good steel, not induction hardened so it can be sharpened, couldn't get a better saw for the price.