This is a very rare early Colt transitional Model 1911A1 pistol manufactured and delivered in 1937. There were only 2,349 blued Colt Model 1911A1s made in 1937, after a 13 year lapse. The pistols are found between serial number 710001 and 712349, with deliveries made to both the U.S. Army and the U.S. Navy. They have all the new Model 1911A1 features but still retain the old slide markings of "MODEL OF 1911.U.S.ARMY". The various changes included: (1) arched main spring housing, (2) radiused clearance on the frame behind the trigger, (3) shortened hammer, (4) lengthened grip safety tang (5) shortened trigger length, and 6) the large diamond shapes around the grip screws were eliminated and now show an all checkered pattern across the grips. The slide still retains the original two-line, two-block Colt markings with the Rampant Colt logo located between the two blocks and the right side still having the old style markings noted above. The full serial number is stamped on the rear of the slide under the firing pin stop. The right side of the frame is roll marked: "UNITED STATES PROPERTY/No 710393". This early pistol does not have the provisional "H" inspection mark above the firing pin stop; however, it does have the single capital "G" production order stamp. It has an all blued barrel marked on the right side "COLT 45 AUTO" and a single "P" proof on the right side of the lug. The right side of the trigger guard is stamped "80," and the left side has the small Colt "VP" verified proof along with a small "P" proof at the top of the trigger guard bow. It has the standard fixed front and rear sights with the checkered thumb safety, slide stop and arched mainspring housing. It is fitted with a blue magazine with a "L" stamped on the lip of the base plate.