Kilo

The Kilo-class submarines are a group of diesel-electric attack submarines designed by the Rubin Design Bureau in the Soviet Union in the 1970s and built originally for the Soviet Navy. Since it was introduced, more than 70 Kilo class boats have been built, and around 60 were in active service as of 2023, not only in Russia but also in Algeria, Vietnam, India, Iran, Myanmar, and Poland.

Excerpt from Wikipedia: Kilo-class submarine. Content available under CC-BY-SA 4.0.