Nib: Medium 14k Gold
c 1943 Golden Pearl Celluloid with Gold Plated Trim / Made in Canada Length Capped 11 cm
1932, 1933, 1934—1948 (1953)
By using a diaphragm rather than a sac, the whole barrel could be used as a reservoir.
as the depression of the plunger pushed on the rubber sac and forced out the air (creating a vacuum)