The Hunter-Seeker control upgrade unit was a GDI support structure in the form of an add-on for the upgrade center used during the Second Tiberium War and the Firestorm Crisis. It was responsible for assembling Hunter-Seeker droids and releasing them when ordered to. The mainframe of the unit was responsible for guiding the droid as well as controlling its detonation procedure.
The Hunter-Seeker control is installed onto an upgrade center's platform. With the phasing out of Hunter-Seekers, the upgrade unit was phased out as well, although similar control methods are employed for repair drones.