One of just 80 manufactured in 1855 with 830 total produced from 1847-1856. Of these, 228 were later altered to the Artillery configuration. The key identifying characteristics are the bayonet guides at the muzzle and lug on the rear of the front barrel band on the right side, as well as the included brass hilted sword bayonet which has a 22 inch leaf shaped blade marked "AMES MFGCO/CHICOPEE/MASS" on one side and "US/ADK/1855" on the other, and inspector marks on the pommel. The front barrel band also has a brass blade front sight on the upper strap and the "L9" marked rear strap notched and locked into a barrel lug. The barrel has "V/P/eagle head" proof marks at the breech and "1855" on the tang. The lock has the standard federal eagle and shield motif over "US" at center and "SPRING/FIELD/1855" on the tail. The buttplate has "U.S." The stock has a "JS" cartouche on the left with "21" on the comb near the buttplate. Collection marking in white under varnish on the bottom of the trigger guard. A fine example of the missing piece in even the most advanced early U.S. martial arms collections!