 A separate subsidiary to manufacture Simms-Vernier couplings (a method of adjusting the magneto's ignition timing) was set up in Lyons, France.During the 1930s the factory developed in conjunction with Leyland Motors a range of diesel fuel injectors, in particular the Uniflow injection pump of 1937.In World War II the company again became the principal supplier of magnetos for aircraft and tanks, also supplying dynamos, starter motors, lights, pumps, nozzles, spark plugs and coils.