Penol’s top-of-the-line pen was the Ambassador series, which started production in 1942. The third series in the line was started around October of 1946 and lasted less than a year. Alongside this production, a new model called the Ambassador #5 was made, using a number of different materials that, interestingly, were the same as the Parker Duofolds made in the UK in the 1940s. (source: Penol Pens and Pencils, João P. Martins & Michael Miloro)
This particular pen is the burgundy and black marbled and was made in June, 1947, as is evidenced by the “647” under the imprint.
Total weight: 16.6 g
Body weight: 9.6
Total length (not posted): 118.3 mm
Total length(with cap): 132.1 mm
Barrel max diameter: 11.6 mm
Cap max diameter: 13.7 mm