The Project 205 Moskit (mosquito) more commonly known by their NATO reporting name Osa, are a class of missile boats developed for the Soviet Navy in the late 1950s. Until 1962 this was classified as a large torpedo boat.
The Osa class is probably the most numerous class of missile boats ever built, with over 400 vessels constructed between 1960 and 1973 for both the Soviet Navy and for export to allied countries. Osa means wasp in Russian, but it is not an official name. The boats were designated as "large missile cutters" in the Soviet Navy.
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