Dimensions: 2.330" OD X 1" High.
Material: Cast brass
The Sigma was a Swiss vehicle built between 1909 and 1914 and took its name from the initials of the full company name; Ste Industrielle Genevoise de Mecanique et Automobiles, Chene-Bougeries.
The cars carried the Greek letter E in the middle of their round radiators. They were medium sized 4-cylinder vehicles, originally with 8/11 hp sv engine. In 1911 the company acquired a license to build the Knight sleeve-valve engine in 18 and 28hp sizes, and they also made 15 and 25hp poppet valve engines