The class 8620 was the first mass-produced passenger locomotive in Japan. With the wheel arrangement 2-6-0 and the same boiler as the 4-4-0 class 6760, it was mainly intended for regular passenger trains with its higher adhesive weight, but still could haul express trains. A Krauss-Helmholz bogie that connected the leading and the first driving axle reduced the rigid wheelbase to only 2.286 mm.

Between 1914 and 1929, multiple manufacturers produced a total of 672 locomotives for the JGR. The Imperial Taiwan Railway got 43 which were designated class CT150. Additionally, small operators received 17, bringing the total number to 732. From the late twenties, they got smoke deflectors. Most were withdrawn in the fifties, but the Haboro coal railway operated some until 1971. 20 have been preserved in Japan and one in Taiwan.