Pick one category for the following text. The options are - company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work. Flutto-class submarine - The Flutto class were a large class of submarines built for the Italian Royal Navy (Regia Marina) during the Second World War.The Flutto's were a development of the 600 Series of medium-sized or seagoing submarines. They were built to a partial double-hulled Bernardis design influenced by war-time experience and construction adapted for mass construction. The Flutto's were good sea-boats with improved internal arrangements hull strength anti-aircraft armament and diving times.
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Mean Of Transportation