You've got another classic old American single-shot-marked "J. Stevens A&T Co.", which stands for J. Stevens Arms & Tool Company. What it likely is Type: Single-shot, break-action shotgun Gauge: 20 gauge Era: Pre-1916 (that exact marking was used before the company name changed) Origin: Chicopee Falls, Massachusetts These were made during the period when Stevens was one of the biggest gunmakers in the U.S. Model identification (why it's tricky) Here's the honest reality: Many of these don't have a clear model number Could be one of several: Early hammer or hammerless single-shot variants Later designs that evolved into models like the 94 From collector discussions: Hammerless versions = usually older (pre-1916) Hammer guns = often later but still early 1900s Bottom line: without more markings, it's usually just identified as a "Stevens single-shot" rather than a precise model. Age estimate Because of the marking: "J. Stevens Arms & Tool Co." = roughly 1886-1916 Most 20-gauge singles like yours: Commonly 1900-1915 range So you're looking at a 100+ year old shotgun.