Consigned by a private collector this watch is preserved in close to new overall condition. It is fitted with the hand-wound caliber 420 movement from which it derives its designation “HW” and a black aviator-style dial with luminous numerals. Caliber 420 remained in production only during a very short period of time.

Zenith was founded in 1865 by Georges Favre-Jacot in Le Locle, Switzerland. It is one of the Swiss watch manufacturers that still today produce their own movements in-house. The celebrated El Primero caliber was released in 1969 and was one of the first automatic chronograph movements. It beats at a frequency of 36,000 alternations per hour (5 Hz) as opposed to the more common standard frequency of 28,800 (4 Hz), rendering it a greater positional accuracy.

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