"SSF-C" (P-989)

The satellites are the first series of so called "Subsatellite Ferrets", low orbit ELINT satellites to pinpoint and characterize different Radar emitters in the Soviet Union and Warsaw pact states. As the proper name of these satellite has not been disclosed yet, they are referred to as "Subsatellite Ferret C" (SSF-C). The SSF-C type series was apparently called Program 989 (P-989).

The SSF-C type satellites operated from a higher orbit (1200–1400 km at about 80.3 to 96.9°) to monitor the ABM radars at Tallinn.

Reportedly the SSF-C type subsatellite ferrets were used in conjunction with the large Jumpseat ELINT satellites, which operated from Molniya-orbits.

These subsatellites were deployed from the propulsion rack of the Agena-D stage of KH-4A Corona, KH-4B Corona reconnaissance satellites and racks mounted on the KH-9 Hexagon reconnaissance satellites. They used two solid-fuel kick-motors to maneuver themselves into their operational orbits after deployment.