SHOTGUN: WINCHESTER MODEL SUPER X MODEL 1, SERIAL NUMBER M21785, OTHER, NOT INCLUDED, 27, 12 GAUGE, SEMI - AUTOMATIC Notes: WINCHESTER SUPER-X MODEL 1 - 12GA Introduced: 1964 Gauge: 12 gauge Action: Gas-operated semi-automatic Manufacturer: Winchester Design: Traditional walnut stock and blued-steel receiver/barrel on many examples Reputation: Known for robust construction, smooth cycling, and relatively simple mechanics. Historical significance: The Super-X Model 1 was produced during the 1960s-1970s and is now regarded as a collectible vintage Winchester shotgun. It was discontinued in 1981.