Made by Fabrique Nationale de Armas, Mexico, and are scarce and desirable to Military semi-automatic collectors. Marked "Sistema OBREGON/Calibre 11.43" on the left side of the slide and FABRICA NACIONAL DE ARMAS MEXICO/ No A 740" on the right side of the frame. It has fixed sights, a grip safety, and the entire length of the top of the slide is knurled. The combination safety hold open device and takedown lever is 3-5/8 inches long, basically covering the rear half of the left side of the frame above the grip. A removable cam block that fits in the frame ahead of the magazine well causes the barrel to rotate to the left moving the three locking lugs out of engagement with the slide. The same locking grooves are used by the mainspring retainer at the muzzle. The mainspring is a major improvement over the Colt 1911 design. The whole mechanism is a single unit and doesn't go flying. The grip straps are serrated and the grips are checkered.

Arsenal refurbished with nearly all of the blue finish with sharp checkering on top of slide, very good grips, with unmarked clip; interior is fine to excellent, and all parts are good, there are minor marks on the grips and slight brightening at operating areas. The Obregon is sought after by collectors and seldom found in this exceptional condition as they saw very hard use in Mexico.