China recently revealed a new version of their most numerous tank, the Type 96. This new model, the Type 96B appears to have a more powerful engine (1,200 HP instead of 1,000 HP), more efficient and reliable mechanical components (especially tracks and wheels) as well as improved armor and electronics. The original Type 96 (also called Type 88C) design entered service in 1997 and Type 96s have since become the primary tank in the Chinese army. That comes to nearly half of the 6,000 medium tanks China still have in service). The next most numerous model, the Cold War era Type 59 is being phased out. There are also about 500 Type 79s and 80s, both of which were stepping stones to the 90 series and several hundred of the latest designs, the type 98 and 99. The Type 96 is apparently going to remain the primary Chinese medium tank for some time as the Type 98 and 99 models are more expensive, heavier and not that much more effective than the Type 96B.
The 50 ton Type 96 has three man crews and modern sensors and electronics. The 90 series tanks are Chinese designs, based on the Russian T-72, a Cold War era design that showed up two decades after the T-55. In 2009 there were about 5,000 Type 59s in Chinese service but by 2016 over half of these had been retired or sold off. Some of the remaining T-59s have been upgraded from being a clone of the Russian T-54 to T-54 and were equipped with Western guns (copy of the British L7 105mm gun, firing depleted uranium shells) and modern electronics. Most Type 59s will not be upgraded and by the mid-2020s all the Type 59s will be gone.