A Heuer Carrera manual wind steel cased gentleman's chronograph wristwatch, Ref. 73453, circa 1970s, with 17-Jewel Valjoux 7734 caliber movement, signed on bridge 'Heuer Leonidas SA', the signed blue grey dial with baton hour markers, date aperture at 6 o'clock, two white subsidiary dials for running seconds and 30-minute recording, painted steel and luminous hands and orange centre stop seconds, framed by an outer tachymeter scale, numbered between the lugs '73453' and '257929', case width 3.8cm, case length including lugs 4.4cm, on an associated steel bracelet with foldover clasp.