This is a fine original example of a Colt Model 1871-72 Open Top revolver; this limited production revolver was the direct predecessor to the Colt Single Action Army revolver. The Model 1871-72 Open Top Revolver is one of the most difficult to obtain of the major Colt revolver types. The revolver has a nickel-plated finish with casehardened hammer, blued trigger and Army size, varnished walnut grip. The revolver has the distinctive Model 1871-72 features which include: (1) lack of conversion breech plate, (2) straight line cylinder and (3) Mason-Richards type barrel with integral rear sight. The rimfire firing pin is attached to the left side of the hammer by two rivets, and the loading gate is held open by a flat spring attached to the side of the frame above the trigger screw. The hammer spur is knurled with a bordered edge. The left side of the frame is roll-stamped: "-PAT. JULY.25.1871-/-PAT. JULY.2. 1872.-" in two lines. The top of the barrel is roll-stamped with the legend: "- ADDRESS COL. SAML COLT NEW-YORK U.S. AMERICA-" in one line. The cylinder is roll-engraved with the Texas Navy battle scene and "COLT'S PATENT NO." The full serial number "3641" is located on the bottom of the barrel lug, the frame, the trigger guard and the back strap. The partial serial number "641" is stamped on the cylinder. All of the visible serial numbers match.