Sterkh was developed as a replacement for the older Nadezhda system. Unlike their predecessors, Sterkh satellites do not carry navigation systems, since this function has been taken over by GLONASS. Sterkh satellites are smaller than their predecessors and were designed to be launched as secondary payloads with other satellites.
The satellites have a mass of 160 kg. Their overall dimensions are 750 x 1350 x 2000 mm in shipping condition, and 976 x 2957 x 10393 mm in operational condition, with opened solar panels and risen gravitational bar. The satellites incorporate the air-borne radio rescue complex RK-SM. They are expected to have an operational lifetime of 5 years. The satellites are designed and manufactured by Production Corporation Polyot.