Very nice and certainly an interesting gun as I don't remember ever seeing one marked like yours. Having it dept. marked #1 is interesting and I would recommend that you obtain a letter from Colt to see whom it was shipped to. Your gun dates to 1926 and this was the end period for the Army Specials as Colt changed over to the Official Police about the same time. What is the barrel length, 5" or 6" ? Should you ever decide to part with it please keep me in mind and thanks for sharing.