The factory letter indicates the carbine was received by the warehouse on October 26, 1877, and shipped out on November 5, 1877, on order 10545. The underside of the stock behind the tang is stamped with a banner cartouches that contain the script letters "AOS". Experts believe that this cartouche was a marking applied to some of the nearly 12,000 Model 1866 carbines in 135,000-148,000 serial number range that were sold to a location in South America (possibly Argentina) in 1877. This marking is described and illustrated on page 65 of "THE WINCHESTER BOOK" by George Madis. The carbine has the distinctive brass receiver and buttplate. The barrel, magazine, barrel bands, bolt and loading gate are blued, and the hammer, trigger, and lever are color casehardened. The stock and forearm are straight grain American walnut. This carbine has the Third Model features which include less pronounced drop in the receiver profile ahead of the hammer and serial number located on the lower tang behind the trigger. The carbine has the early style front barrel band with integral front sight blade. The barrel is fitted with the second style, two-leaf rear sight. A staple-mounted saddle ring is located on the left side of the receiver. The carbine style brass buttplate has a sliding brass trapdoor compartment that contains a three-piece steel cleaning rod with brass tip. The top of the barrel is roll-stamped with the two-line legend: "WINCHESTER'S-REPEATING-ARMS. NEW HAVEN. CT./KING'S-IMPROVEMENT-PATENTED-MARCH 29. 1866. OCTOBER 16. 1860." between the lower barrel band and the rear sight. A small "S" is stamped on the top of the barrel between the rear sight and the receiver. Madis noted that this marking is seen occasionally on Model 1866 rifles and carbines in the 150,000-155,000 serial number range and appears to be an assembly or fitting mark. The serial number, "147401," is stamped in script letters on the lower tang behind the trigger. The previously discussed "AOS" banner cartouche is stamped on the underside of the stock about 2 1/4 inches below the receiver tang. There are no caliber markings on the cartridge elevator.