Vacheron Constantin 498

Caliber 498 is an automatic movement manufactured by Vacheron Constantin between 1954 and 1956. It features a unidirectional 360° rotor with sub-seconds display, 17 jewels, and operates at 18,800 vph. The movement belongs to Vacheron Constantin's 4xx caliber family but was not produced in-house—it was sourced externally and finished by the manufacture. Production lasted only two years, making it rare among collectors.