Historically a supplier of watches to Italian and various international armed services, and specifically chronographs to the Italian Air Force, A. Carelli operated out of Via del Corso, Rome, where the chronographs could be checked, serviced and adapted to flight mission requirements.
It didn’t matter if the fighter jocks were flying Fiat, Caproni or Savoia-Marchetti, the one common bond was the Cairelli chronographs they wore on their wrist. While A. Cairelli still makes chronographs like the Traguardo, Doppiocrono and Aviomatic today, they tend to be built on base ETA 7750 movements thus making vintage chronographs from the 60s and 70s some of the most sought after chronographs from the company.
More importantly, Zenith supplied 2,500 chronographs equipped with the manual winding in-house calibre 146 DP in 1965. The chronographs were water resistant with a soft-iron movement casing giving it some protection from magnetism and at 43mm were fairly large for watches of that era.
Early chronograph movements were designed by the Raymond brothers who opened a chronograph movement manufactory in Les Bioux, Vallee de Joux in 1901. By 1929, it was so successful it eventually assumed the name- Valjoux. By 1960, Zenith acquired the Martel Watch company based in Les-Ponts-de-Martel, the calibre 146 which it made was first used in Universal Geneve chronographs beginning production at the turn of World War II in 1934. Calibre 146 DP with the denomination “Cronometro Tipo CP2” and equipped with a 30 minute rather than a standard 45 minute counter, the movement with an antimagnetic inner case was phased out in 1971 with the development of Zenith’s own self-winding chronograph, the calibre 3019 PHC.