Complex sentence: The first three D.520s were assigned to 2 ° "Stormo" based at the Torino-Caselle airfield, where they were used for the defence of Torino's industrial area.
Split into simpler sentences: The first three D.520s were assigned to 2 ° "Stormo". Based at the Torino-Caselle airfield, they were used for the defence of Torino's industrial area.