There are actually 3 types of tanks in this video. ZTZ-99 original, ZTZ-99 type 1, ZTZ-99 type 2, ZTZ-99A. 0:26 0:34 are ZTZ-99 original with no additional armor. 0:51 is ZTZ-99 type 1, this one is the rarest of all types and quickly replaced by type 2. 1:08 2:25 are ZTZ-99 type 2, got improved armor and turret based on type 1. 0:42 1:02 are ZTZ-99A, this is a totally new tank with brand new chassis,turret and armor but inherited the name of ZTZ-99. The exterior difference between Type1&2 are: type 2 have no bump on turret and have a step on front end. ZTZ-99A is higher& boxier, have a bigger turret. The space between wheels are equal and chassis is shorter.