 The first design was a 6.35mm blow-back design based on the Browning 1906.This was the Brevetto 5 (Italian for "Model" or "Patent" number 5).Galesi Arms would continue to do more designs including the Brevetto 9 (a longer version of the Brevetto 5) and the 500 series, which included 14 designs ranging from Brevetto 503 to Brevetto 517.