This US&S M1911A1 was part of a 55,000 military contract W-ORD-2211 from May 5th, 1942. Initially the order was for 200,000 pistols but was revised on July 9th, 1943.
The Union Switch & Signal Company of Swissvale, Pennsylvania was a supplier of railway signaling equipment, services and systems. During WWII the US government was utilizing companies who were proficient at manufacturing and would utilize them manufacturing needed items required for the war effort.
Union Switch & Signal would answer this call by delivering 55,000 pistols during 1943. They would then move on to deliver much needed M1 Carbine components.
This pistol bears the inspector mark of "RCD" for Lt. Colonel Robert C. Downie. He was the Army Inspector of Ordnance at the Pittsburgh Ordnance District from July 1942 to October 15th of 1945. He would oversee the entire M1911A1 production from Union Switch and Signal.