Drawing inspiration from the British STEN gun, the M3 was developed as a high-speed, low-cost substitute for the Thompson family of submachine guns. The M3A1 further streamlined the process, with the biggest change being the removal of the lever action cocking mechanism in favor of a bolt slotted to be retracted by hand. While lacking the aesthetic charm of the Thompson, the M3 and M3A1 were serviceable weapons, and would be America's go-to SMGs through World War II and following conflicts. Blade front and peep rear sights, model nomenclature and Guide Lamp markings on the left side of the magazine well, combination dust cover and safety on top, textured pistol grip with integral oiler, and a two-position telescoping buttstock.

Very fine, with 95% of the arsenal refurbished dark gray parkerized finish, showing mild spotting on the barrel and around the sling mounts, as well as light handling marks. The stock and chamber cover both retain much of their matte black finish, with flaking showing a gray and brown patinated base steel. 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 479.