Serial number range: 270001-492000 (1935-1939, approx. 6,504 produced). Production by year: 1935: #270001-270004 (4 units); 1936: #288001-290000 (2,000 units); 1937: #375501-377000 (1,500 units); 1938: #426001-427000 (1,000 units); 1939: #490001-492000 (2,000 units).