At the beginning of the 20th century in Montrouge, Paulin Ratier invented the variable-pitch propeller. During the First World War, his company prospered by supplying propellers to the French Air Force. However, after the war, demand declined as civil aviation was still in its infancy. Ratier therefore turned to automobile manufacturing and attempted to adapt his aircraft engine technology for use in cars. After producing just twenty automobiles—half of them equipped with conventional engines—he discontinued production.

Paulin Ratier then converted his factory once again to manufacture the "Citroënnette," a name registered as a trademark in 1924. This toy car was a scaled-down replica of the Citroën 5 HP, one of the brand's most popular models at the time. The Citroënnette proved to be a great success and was produced in seven different versions. It was marketed by André Citroën as a promotional tool. His goal was to capture children's imagination so that, once they became adults, they would choose to buy a Citroën automobile—the same brand as their childhood toy.

From 1929 onward, Paulin Ratier resumed the production of aircraft propellers, this time for the growing civil aviation industry.

- Battery-powered headlights 
- Black moleskin seat 
- Reciprocating ("back-and-forth") pedal mechanism 
- Link-chain transmission