sentences:  Five navy yards were employed in series production of the class, three in Leningrad (#189, #194 and #196), one in Nikolayev (#198) and one in Gorky (#112).Boats for Pacific Fleet were assembled from prefabricated sections, delivered by railroad, in Vladivostok's plant #202.The first boat was completed in the beginning of December 1935, and made her first dive on December 15.