The Mk 92 system assigns targets via the ship's air search radar, and surface search radar or from the MK 92's own search radar capabilities. The system has two or three radar sub-systems depending on the model. The first two are combined into a single system called the Combined Antenna System or CAS is used in all models. The CAS has a track while scan radar (Search) and a tracking radar both housed in an egg shaped randome. The radars can search for, track, and illuminate targets. There is also a third radar for target illumination referred to as the Separate Target Illumination Radar or STIR. The STIR is a radar developed from the AN/SPG-60 radar that is part of the Mk 86 gun fire control system.