.22 LR. 5" barrel length. SN: NSN. Blued metal finish with polished flats and matte rounds featuring bright polished chamber. .22 Caliber conversion unit for Colt 1911 pistols featuring the two-piece barrel assembly and mounting adjustable target rear notch and front blade sights. Left slide struck CONVERSION/UNIT followed by COLT AUTOMATIC/CAL. .22 L.R. {Rampant Colt}. Right slide marked in a single line COLT'S MFG. CO. HARTFORD CT. U.S.A. Comes with two-piece barrel, recoil spring, bushing, ejector, recoil spring guide, and COLT marked detachable box magazine.