Pen Model: Mallat Integral

Mallat was one of the major fountain pen manufacturers in France from World War I until well after World War II, building from roots in the late 1800s. They made ebonite pens, starting with the Regulier eyedropper, the Sureté safety filler, and the Automatic lever filler. Mallat shifted to celluloid in the 1930s, with lever and button fillers, producing standard French pens.
In the 1930s, Mallat introduced the accordion filler, in part to control costs, as well as to respond to public demand to see ink in the pen. The Integral, which first appeared in celluloid in 1936 with a glass topped accordion sac. Their post WWII success was found with plastic pens, the Plexigraph piston models, and with Integrals, now with plastic tops on the accordion fillers.
Mallat, as a sinking move, purchased the moribund but formerly elegant Edacoto brand in the 1960s, but the move did not succeed. Mallat was purchased by a multinational firm in the late 1960s and the brand disappeared.