An Italian Propaganda Postcard for "La Decima Flottiglia Mas." The Decima Flottiglia MAS (Decima Flottiglia Motoscafi Armati Siluranti, also known as La Decima or Xª MAS) (Italian for "10th Assault Vehicle Flotilla") was an Italian flotilla, with marines and a commando frogman unit, of the Regia Marina (Royal Italian Navy). These were the commandos who employed the one-man submarines. After 1943, the part of the Decima MAS which was stationed in the north of Italy joined the Mussolini government and fought alongside the Germans until the end of the war. Dramatic artwork card depicts artwork of an X Mas high-speed torpedo boat.