ShL-01 (Russian: Шкала латы, shkala laty - scale plate armor) armor is an armor type devised by Soviet military strategists. Based upon lamellar designs of the medieval era, it was designed to be flexible and protective at the same time, much like chain mail.
ShL-01 was developed throughout the mid-1990s and early 2000s as a direct response to the indecisive nature of the first Sino-Soviet war in the 1980s. Desiring greater survivability rates against the intermediate rounds most of the world had adopted, ShL-01 was rated to be resistant to the 5.45mm rounds the Chinese AKM clones made use of -- that is to say, the rounds would hypothetically either deflect on impact, or be slowed enough by the overlapping plates of the armor such that the wearer would not suffer the effects of the round tumbling.
Although effective in its purpose -- by making use of a number of synthetics, metals, and ceramics -- ShL-01 was expensive and slow to produce. Because of how complex it was to produce, only the base components of each set of armor could be machine-made. Every single suit had to be assembled by hand, which made it unfeasible for rapid mass-production. This, in turn, meant that the adoption rate among the Soviet military was slow, starting with the elite and standing units. Further, each suit of armor would be reissued when its original owner either retired, was discharged, or died.
Despite its effectiveness, ShL-01 proved to be a relative bit part in the grand scheme of all of the conflicts in which it was employed. Casualty rates during the second Sino-Soviet war remained roughly the same in context (the Chinese military, though far less advanced, was capable of fielding vastly more soldiers than the Soviet military). Only against a foe of similar size and capabilities, such as the German military during The European Wars, did ShL-01 play any significant role, reducing the number of combat deaths to a fourth that of the German forces despite similarly-sized forces.