Their participation in the automotive business was far from ended, however, and in 1913, with the help of F. Berwick, the London-based UK importer of Corre La Licorne cars, they obtained finance in London for the launch of a new automobile manufacturing company called Sizaire-Berwick.

Orders were good and the company received backing to move to larger premises from bicycle importers Hammond et Monnier who soon afterwards sold the firm to the Duc d'Uzes and from 1907 the family crest appeared on the radiator surround.

After the departure of the Sizaire brothers the technicians at the business switched to a four-cylinder engine,[1] initially using a bought-in 1847 cm3 Ballot unit, but did not result in significantly increased sales.

After the war, production restarted with a new company, Société des Nouveaux Établissements Sizaire et Naudin, making Ballot-engined cars based on prewar designs.

The manufacturer took a stand at the Motor Show in October 1919 to exhibit a four-seater torpedo" bodied Type D car with a 2,820 mm (111.0 in) wheelbase, and powered by a four-cylinder 2292 cm3 engine.