This revolver is one of approximately only 7,000 manufactured circa 1872-1873. The Model 1871-1872 Open Top was a direct predecessor of the hugely successful Colt Single Action Army Revolver, and these were some of the first Colt cartridge revolvers available in the West. These revolvers often saw hard use on the western frontier, remaining in use as working guns well into the period of dominance of the Single Action Army. The top of the barrel is marked "-ADDRESS COL. SAML COLT NEW-YORK U.S. AMERICA-". The left side of the frame is marked with the two-line 1871 and 1872 patent marking, and the cylinder is roll engraved with the Naval Battle of Campeche scene and "COLTS PATENT No. 634". The matching serial number is marked on the barrel, frame, trigger guard, and back strap.