Article mentions two Kilo class boats: The Project 877 or Platus diesel-electric submarine, better known in the West as the Kilo class, was designed in the early 1970s for the anti-submarine and anti-ship defense of Soviet naval bases, coastal installations and sea lanes, and also for the patrol and surveillance tasks. First delivered from the shipyard at Komsomolsk in eastern Siberia, but then built in the western USSR at Nizhny Novgorod ant the Admiralty Yard in Leningrad (now St. Petersburg), the boat is of the medium-endurance type and the first example was launched in 1979 for completion in 1982.

https://www.military-today.com/navy/kilo_class.htm