A total of 10,500 Colt Government Model pistols were acquired by the British government between October of 1917 and April of 1919. This particular pistol was likely shipped in the first half of 1918 based on p. 265-266 of "The Government Models: The Development of the Colt Model of 1911" by Goddard. It is a Colt Government Model outfitted with a .455 barrel and magazine, with a set of crossed pennant and broad arrow military stamps, "crown/G2/A", and "R.A.F." markings on the left side of the frame, "COLT AUTOMATIC/CALIBRE 455" on the right of the slide, along with the standard commercial markings and the special "W" prefix serial number. It is fitted with fixed blade and notch sights, with a long smooth trigger, wide checkered hammer, short grip safety, checkered grips, a matching numbered two-tone magazine with "CAL.455/ELEY" and a broad arrow marked lanyard base, and the proper "shelf" for the .455 case rim in the chamber hood.