The Colt Government are direct 3rd and 4th generation descendants of the "often imitated but never duplicated" Colt M1911 classic automatic pistol. It was selected as the U.S. military service sidearm in a head to head competition. The superior Colt was found to be, more reliable, more durable, more easily disassembled, less fatiguing and more accurate. The O1991 model features a Series 80 firing system.