The Fox pin-guns came in three phases that I know of. 1st came the one marked "Sterlingworth Company" with a Wayne Junction address and no mention of Fox. 2nd was one also marked Sterlingworth Company with the Philly address. Finally came one marked just Sterlingworth with the Fox name on it. All were made over a 17 month (I think) period and the all later Sterlys were done without the recessed pins...Geo