The so called “Jo Siffert” after the famous Formula 1 driver who was wearing that racing-chronograph while his active time. This piece is the Mk5 version, which for some collectors is the most beautiful one, as the left subdial still has the early 3,6,9,12-scale but allready combined with the nice brushed blue hands. The lume of dial and hands is still the original tritium. In this piece there is also the earlier calibre 11 automatic-movement doing it´s work. All matching and fully authentic in an unpolished case engraved with a 204xxx serialnumber. This watch comes on it´s original Gay Freres/Heuer Bracelet, signed 3/72.