This is the first in a series of four Standard model revolvers. Chambered for .30-caliber rimfire. Earlier model has an octagonal 3.125" barrel; later, a round 3" barrel. There are round and octagonal barrel variations (with unfluted cylinders) and round barrel variations (with short and long fluted cylinders). All barrels are ribbed and tip up for loading. They have plated brass frames and barrels are nickel-plated. Bird's-head grips are of rosewood or hard rubber, bearing the monogram "M.F.A. Co." inside a star. There is a spur trigger. Markings "J.M. Marlin-New Haven Ct." appear on earlier octagonal barreled models. "U.S.A. Pat. July 1. 1873" was added to later round barreled models. All barrels are marked "XXX Standard 1872". Approximately 5,000 of all types manufactured between 1872 and 1887.