Well the speedo internals are metric. Invented by the French.
Actually it a bit of very early badge engineering - original designer and maker was Jaeger.
The history of the development of the Jaeger car clocks begins back in 1880 when the great French watchmaker Edmond Jaeger (1858-1922) established his company in Paris. He devoted his life to developing mechanisms for measuring speeds and was a pioneer in the development of chronometers, tachometers and automobile and cockpit clocks.
At the beginning of World War I, Edmond Jaeger collaborated with Jacques-David LeCoultre to develop onboard instruments intended for aviation. The speedometers and tachometers manufactured in the Vallée de Joux soon came to equip most planes in the French, English and U.S. air forces of this period. These instruments were so highly regarded during the first world war that many Germans equipped their planes with Jaeger instruments obtained from downed English and French planes. It is said that one of these instruments was found fitted to the plane of the famous German ace Manfred von Richtofen (the Red Baron) when it was shot down.
At the start of the 1920s, Jaeger and LeCoultre decided to utilise their experience and skill in producing aviation instruments in a new venture involving the production of dashboard instruments for the automobile industry. In addition to producing automobile speedometers and tachometers they also began to produce high quality 4 and 8-day automobile clocks. This new venture proved to be remarkably successful with large numbers of automobile instruments produced and exported throughout the European and American automobile markets. To avoid the protectionist measures adopted by the British government, the two entrepreneurs founded a company in London specialising in dashboard instruments, which at one point employed up to 700 people. In parallel, they laid the foundations in Paris for the future Jaeger factories in Levallois, which would host a 1800-strong workforce.
After WWI, the British subsidiary (British Jaeger) of Jaeger of Paris secured the manufacturing rights to the chronometric mechanism and manufactured these very reliable chronometric mechanisms at a factory at Willesden. In 1927 British Jaeger was purchased by Smiths Industries Limited. These chronometric mechanisms were incorporated in the speedometers and tachometers of English race cars and expensive English sedans.
The Jaeger car clocks, speedometers and tachometers have a reputation for reliability and quality and were utilised by many of the greatest names in the automobile industry in 1920s and 1930s including Bamford & Martin (which would later become Aston Martin), Bugatti, Bentley, Delaunay, Rover, Citroën, Renault, Delage and Vauxhaull. All prestigious French cars were equipped with Jaeger dashboard instruments, as were half of all cars being driven in England. Almost all the the racing cars of this period were equipped with Jaeger instruments.
