Manufactured in 1874. This revolver was inspected by Orville W. Ainsworth and is stamped with his distinctive "A" sub-inspectors mark on the bottom of the barrel, below the serial number on the trigger guard, on the cylinder and on the top of the back strap. These nickel plated Cavalry Models were plated for issuance to Indian Scouts, special order "officers" revolvers, surplus militia revolvers sold back to Colt or nickeled by commercial businesses and U.S. Navy revolvers. Kopec's "The Story Of The Colt Single Action Army Revolver" identifies the largest single block of nickeled Cavalry revolvers as occurring in the 11,800 through the 14,230 serial number range, all manufactured in 1874 and all inspected by Ainsworth. This specific revolver, serial number 12,661 is listed by serial number on page 21 of "Colt Cavalry and Artillery Revolvers" by John Kopec and H. Sterling Fenn. The top of the barrel is marked with the one line address and the left side of the frame is marked with the two line, two patent dates followed by "US". There is a "P" on the bottom of the barrel ahead of the cylinder pin and on the cylinder. The matching serial number is marked on the bottom of the frame, trigger guard and back strap, and the partial serial number "2661" is marked on the bottom of the barrel under the ejector housing and on the cylinder. Standard blade front and frame notch rear sights, and fitted with a smooth one piece ivory grip and lanyard swivel on the butt.