Very rare Swiss steel chronograph with register Circa 1950

Steel chronograph Rattrapante by Longines
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A rare Swiss steel chronograph Rattrapante pocket watch with register, circa 1950.
Ankerchronometer with 21 jewels, Geneva striping, split-seconds chronograph with 30-minute counter. White enamel dial with Arabic numerals and blued steel hands. Plain case, punched serial number and reference to the hinged back. Matching numbers on case and movement, dial and movement signed. Comes with the original box.
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Diameter: 66 mm
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Weight: 268 g
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Signed: Longines
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These high-quality Longines timepieces were used in the Olympic games and are therefore often named the Longines Olympia.