Air defense gun ZSU-"Shilka" is equipped with the quad-mounted 23-mm automatic anti-aircraft gun AZP-23 "Amur", capable of engaging targets at altitudes up to 1.5 kilometers and at a range of up to 2.5 kilometers.
The proposed upgrade of the ZSU-23-4 "Shilka" implies almost complete replacement of the elements of radar and instrumentation complex (RPK), including: radar 1RL33, counting and resolving unit, sighting line stabilization system and shot line stabilization system.
Instead of the radar and instrumentation complex, the self-propelled anti-aircraft gun mounts the modern Strizh-M3 optoelectronic instrumentation system, which not only makes it possible to significantly increase the accuracy of the calculated coordinates of the preemptive point and other parameters, including the range of target detection, which affects the effectiveness of combat use, but also, due to the passive operation mode, it improves the stealth and survivability of the air defense gun.
An additional result of the modernization was a reduction by almost two tons in the overall weight of the combat vehicle, which reduced the load on the traction engine and gave the crew a place to put their weapons, ammunition, food and personal belongings of the crew.
In addition to the modernization of equipment the air defense gun. in the course of work is being modernized GM-575: the system of primary power supply, automatic fire extinguishing system (transfer system on the fire extinguishing mixture of carbon dioxide instead of toxic freon "composition 3.5") and the system of monitoring the area in conditions of poor visibility of the mechanic-driver.