Developed in the 1930s, the sleeve pistol of Elmer Carlstrom of Chicago, Illinois, uses a mechanism similar to many pen guns of the era, with a screw-mounted smoothbore barrel and a pre-cocked spring loaded striker for firing. Unlike a pen gun, the E. Carlstrom is equipped with a rifled barrel, a steel reinforced leather base, which straps to the underside of the user's forearm, and a light cord that attaches to the trigger mechanism; depending on user preference, this line can be secured to a ring on the finger and automatically discharged when the appropriate hand is flipped upward, attached to a dummy cuff (see pic) button to be pulled by the off-hand, or other imaginative combinations. Both sides of the metal plate that secures the pistol to the brown leather base are marked "E. CARLSTROM CHICAGO", with one side additionally marked "35", with a knurled cocking knob and barrel ring. Fitted at the front and rear of the base are black leather straps, with a buckle on the front and the rear. Manufucture: E. Carlstrom Model: Sleeve Pistol BBL: 2 1/2 inch round rifled Gauge: 38 Serial Number: 35 It shows areas of spotting & rust. Edge wear noticable on the leather straps. Mechanically good. 2 original screws have worn threating (see pics). I have added 2 screws to make functional. A unique piece of Firearms Curiosa.

I have no idea. This antique gun was a gift from a friend.