A FOUR COLOUR CODED CHRONOGRAPH

A FOUR COLOUR CODED CHRONOGRAPH, c.1930, the white dial with black, red, blue and green Arabic numerals enclosing two subsidiary dials and inscribed UNIC, the outer rim inscribed Kilometres a l'Heure, with unnumbered jewelled movement, hinged cuvee and plain case both stamped 800 NB Apparently these four colour coded watches were used for yachting purposes