Rare Swiss observatory chronometer watch Circa 1966

Open faced steel pocket watch by Nivarox
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A rare Swiss observatory chronometer Nivarox no. 408, circa 1966. 4 times tested in Neuchâtel and Geneva from 1966-1969.
Steel case with both sides glazed and transport case made of wood. Lever movement, chronometer movement, 36,000 A/h, Geneva striping, caliber Longines 260, modified by Nivarox. Silvered dial with Arabic numerals, sunk subsidiary dial for the seconds, blued steel spade hands and inscribed CHRONOMETRE.
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Diameter: 70 mm
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Signed: Nivarox