From 20:00 shows different APS systems. From 21:00 - Drozd. 22:45 - Arena.
APS system from 1960s, placed on T-55.
Arena was designed for T-80U. Arena's munitions were fired upwards in order to hit incoming projectile with fragments and then ground will "catch" all of them in specific area around the tank, to decrease danger for other troops in formation. Design work were completed shortly before 2000s.
Modernized Arena APS (from 24:00). Amount of intercepting munitions were decreased to 8-12, but each of them is now capable of changing trajectory/rotate in flight. Each munition is equipped with impulse engines. In video Head of department of KBM claims that it gives 360 degrees protection and capable to intercept Javelins, Spikes and other top-attack ATGMs.