Rare 1964 IWC Ingenieur ref 666 AD, cal 8531 first generation ( second dated 1967 n after ).
21J. T SWISS T dial Antimagnetic to 80000A/m; 10 atm ; civilian version of Mark XI ! PAT.APPL Sn 1714650 dated 1963-64. Staybrite case sn 1823750 , all original n rare fish symbol! One of best IWC indeed !
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