The new generation bus, designated 4V, had a height of 2.8 meters and a span of solar panels of 6.7 meters. The central section of the bus, with the height of one meter and the diameter of 1.1 meters, contained propellant tanks for the main propulsion unit. The main engine was encircled by a conical instrument compartment with the diameter of 2.35 meters at the base, which also served as an interface with the upper stage of the launch vehicle.
The 4V spacecraft was equipped with a flight control computer responsible for processing information from the star and Sun sensors and sending commands to the gyroscopes of a three-axis attitude control system.
A pair of 1.25 by 2.1-meter solar panels provided electrical power.
4V orbiters carried following scientific payloads:
A Soviet-built ultraviolet instrument to study the clouds in the Venusian atmosphere