Approximately 4,200 Type I Gwyn & Campbell "Union Carbines" were manufactured circa 1863-1864, also known as "Grapevine Carbines." Gwyn & Campbell carbines were issued to a number of Union cavalry units primarily from the Midwest and West. Manufactured by Edward Gwyn and Abner C. Campbell, the Gwyn & Campbell was the successor to the Cosmopolitan carbine, and manufactured in the same factory out of Hamilton, Ohio. The Type I variation of the Gwyn & Campbell is distinguished by its long serpentine shaped hammer and loading lever. 1,000 yard folding ladder rear sight, blade front sight, and left mounted sling bar and ring. Matching serial number "300" marked underneath the breech end of the barrel, frame, and breech block.