I recently got this small rocket motor. It's about the size of a large coffee can. The base says PACS-1 Ejection Motor with a logo underneath that I believe is the Atlantic Research Corporation logo. My guess is that it's from the 60-70's based on the hand engraved serial numbers, coffee stained base, and light patina that had accumulated on the nozzle half of the motor. It did clean up pretty well though as seen in the above photo. It looks like a large central nozzle surrounded by the four smaller nozzles (two of which are canted 45 degrees and all the smaller ones are plugged). I'm guessing the the nozzle consisted of at least a couple of parts and that the convergent section and throat were recessed. Those sections are not included so the visible divergent section is only part of the nozzle included. The two halves unscrew and the gold anodized half is lined with rubber and has a variety of inspection stamps. There is also a central threaded "neck" were the igniter is likely intended to go. I'll post some more pictures when I get a chance.