In 1968, GOI began developing the OB-424 lens for the Soviet medium-format Salyut camera system, which had already been in serial production since 1957. This design later evolved into the legendary Jupiter-36, which only entered series production around 1975 at the Zavod Arsenal factory for the Salyut-C / Kiev-88 / Kiev-60 camera systems.The lens offered here is a true early prototype. It is noticeably heavier and larger than the later production version and features a different internal optical construction, representing an important transitional development stage before the well-known Jupiter-36 was finalized.The example is in very good condition. The glass is clean, focusing is smooth, and the diaphragm ring operates softly and evenly. It comes with the original front lens cap and a Salyut camera body, most likely also used for testing purposes at the factory.A rare and historically significant GOI prototype. SN: 690181