Neptune are hard to ID. The only way I was able to ID the one I just had was from the blue color and that it was setup for a starter recoil which made it a Mighty Mite 700. Tubs was correct about the numbers being part numbers. There were no ID markings on the ones I have encountered. If that is the same for all, then I find it odd that Muncie made this their business model. They sold a crap load of these little putters over 50 years. You do not see them come up for sale often so either they are all still in hiding or have been thrown away over the years. Parts are scarce. Good luck in getting it going. Reach out if you need help.
