Only a few thousand were manufactured from the late 1870s to 1880s. The revolver has an exposed cylinder pin, scooped cylinder flutes and loading gate. The barrel rib has the Hopkins & Allen two-line legend, and the frame has the two-line MH&Co. address and "38 CAL." Matching serial numbers on the grip frame, right grip panel, cylinder and barrel. The extra 5 1/2 inch barrel in .38 caliber has the H&A two-line rib legend and the number "3239."