In May of 1942 the U.S. government initially placed an order with Union Switch & Signal Co. for 200,000 Model 1911A1 pistols, an order which was later revised to 55,000 pistols. All 55,000 of the Union Switch & Signal Co. made Model 1911A1 pistols were delivered throughout the course of 1943, while World War II was still at its height. According to the table on p. 144 of "U.S. Military Automatic Pistols: 1920-1945" by Meadows, the serial number for this specific pistol is listed in a shipment of 10,828 pistols in June of 1943. These Union Switch pistols often quickly found their way to the front lines and generally saw hard use through the remainder of the war, making benchmark examples like this one incredibly scarce. The slide is marked with the "USS" monogram and "U.S. & S. CO./SWISSVALE, PA. U.S.A." on the left side, with Robert Downie "R.C.D." inspection initials on the left of the frame, and standard U.S. government nomenclature on the right, in the distinctive Union Switch & Signal style. The correct full blue barrel is marked "HS" on the right of the lug and "P" on the left. It is fitted with blade and notch sights, thin checkered hammer, short stamped trigger, long grip safety, arched checkered mainspring housing with lanyard loop, correct Keyes Fibre checkered grips, and an "R" marked full-blue magazine.