OMEGA chronograph Speedmaster so called 'Mark IV Professional', self winding, reference-no. 176.0012, Switzerland around 1980, solid stainless steel case including original bracelet, case back with Seamaster Logo screwed down, display of hours, minutes, constant second, day, date, 24-hours & chronograph, mineral crystal (scratched) with tachometer graduation, movement copper coloured, 17 jewels, central rotor, calibre 1045, flat rim balance, flat hairspring, Kif- shock-absorber, measures approx. 45 x 42 mm, length approx. 20 cm, overhaul recommended at buyer's expense, condition 2-3, literature 'Reise durch Zeit' written by Marco Richon page 612

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