Comparing: 121B vs. 121

The upgraded version of the 121 Chinese medium tank, developed in the 1960s. Unlike the prototype, the 121B was equipped with a modern 105-mm rifled gun, improved suspension, and reinforced front armor. The vehicles of this modification were equipped with infrared lamps and a laser rangefinder. The 121B aiming system had a higher firing accuracy than that of the Type 59.

Development began in 1962 on a new medium tank based on the Type 59. The new tank was expected to feature improvements in firepower and armor protection. However, the project was canceled shortly after. Some technical innovations were applied later, in the development of the Type 69 tank. All 121 tank prototypes were destroyed during Chinese nuclear weapon testing.