Originally manufactured by Colt as a Model 1921 Thompson SMG, one of a number stuck in inventory due to sluggish sales; while today the Thompson is recognized as an American classic and one of the all-time finest "heavy metal" SMGs, at the time it was a novel, untested and expensive weapon, and few were willing to roll the dice. The U.S. Marine Corps was an early adopter, and the firm attempted to capitalize on the connection by adding "U.S. NAVY" markings to their 1921s, updating the features based on USMC feedback, and overstamping the "1921" to "1928" to match their newer model. According to Herigstad's "Colt Thompson Submachine Gun Serial Numbers and Histories", this particular Thompson was sold to the Stamford (Connecticut) Police Department in 1932, and remained in their inventory until 2003. Blade front sight on the unmarked Cutts-style compensator and a folding Lyman rear sight, showing the signature cooling fins on the barrel, dual hardwood pistol grips, and a quick-detachable hardwood buttstock. The left side of the receiver has the aforementioned "U.S. NAVY" model markings ahead of the 5-line address and caliber markings, with the Thompson "bullet" logo on top and the Auto-Ordnance address and 6-line patent markings on the right. The trigger group is numbered to match the receiver on the underside, with separate selector ("FULL/AUTO" and "SINGLE") and safety ("FIRE" and "SAFE") levers. The item is equipped to accept both drum and stick magazines. Magazine not included.

Excellent, with 95% of the original blue finish, showing some mild scratches on the receiver and trigger group, a patch of mixed brown/gray patina on the compensator, and mild handling marks overall. The very fine wood shows a number of dings and scuffs, with a chip absent from the foregrip and a crack in the right side of the buttstock alongside the mounting iron. Mechanically excellent. NOTE: This weapon is a National Firearms Act (NFA), fully transferable Class 3, which is registered with the Bureau of Alcohol, Tobacco, Firearms and Explosives, (BATFE) that is classified as a "Curios or Relic" as defined in 27 CFR, 478.11. These weapons are still subject to the provisions of 18 U.S.C. Chapter 44 and 27 CFR part 478.