This is an excellent example of an original, fully automatic Colt Model 1921 (AC) Thompson Submachine gun. This particular machine gun is a mid-production model with only 15,000 manufactured in total with almost all of the later converted into the M1928A1 configuration. The Colt/Thompson SMGs were the high mark in submachine gun manufacturing. These were true works of art in that they were beautifully machined and hand fitted making them function beautifully. This weapon is documented on page 399 in the book "Colt Thompson Submachine Gun Serial Numbers and Histories" by Gordon Herigstad, as originally being sold to the Trenton N.J. Police Dept in June 1925 with three other SMGs, then resold three more times to various collectors. The receiver is marked "MODEL OF 1921/4001" along with the standard five-line factory markings: "THOMPSON SUBMACHINE GUN/CALIBRE 45 AUTOMATIC COLT CARTRIDGE/MANUFACTURED BY/COLT'S PATENT FIRE ARMS MFG. CO./HARTFORD CONN. U.S.A." The right side is marked "AUTO-ORDNANCE CORPORATION/NEW YORK U.S.A." followed by the standard five-line patent dates. The matching trigger housing is marked: "FULL-AUTO" and "SINGLE" along with "FIRE" and "SAFE" and is serial numbered "4001" on the underside. This model is an "AC" version which identifies it as a standard grade with the patented CUTTS compensator on the barrel. It also has the distinctive finned barrel, fully adjustable Lyman tangent rear sight with sight protectors, the walnut vertical fore grip, and the detachable walnut buttstock with the butt trap which holds an original Thompson oiler. The gun is complete with a newer FBI type black carrying case that is stenciled on the outside with "TRENTON/PD", the original case key, attached to a Trenton identification pin, 1 original Auto-Ordnance 50 round drum magazine (serial numbered 2068), 4 stick magazines (1 Auto-Ordnance and 3 Colts), cleaning rod, small cleaning kit, key, Thompson manual and a Trenton N.J. Police badge and shoulder patch.