Local shop had a couple of early model 10s. One was half price of the other. Both nickel, one had a beautiful finish, the other was yellow and dull. The dull had that yellow sheen indicative of old WD40. I brought home the cheaper one. It was in excellent mechanical condition. I've cleaned a few of these WD40 guns, so I knew what to do. 45 minutes at the bench and I have gun now in better shape than the more expensive one! A little bit elbow grease goes a long way! My guess is somewhere around 61 or 62 model 10-5. Super slick action, older Smiths are really hard to beat.