A Calibre or Caliber is used as a reference to the manufacturer’s movements. The specific movement or internal mechanism of the watch is designated a unique model which becomes the identification number of the time teller. Certain manufacturers tend to use their own identification system to number the in house movement that are developed.
Brands like Omega and TAG Heuer have numbered their calibre as per the intricate movements involved in the watch mechanism. For example, Calibre 3, 5, 6, & 7 are all automatic movements with a slightly different additional function or feature such as a sub-seconds dial at the 6 o’clock portion of the dial (Cal 6) or a second time zone/GMT hand.
Calibre 16 is an ETA 2892 auto with a chronograph module attached. The quickest way to tell if this movement is being used (in any watch) is to look at the crown and pushers on the side of the case. If they are all in line with each other (when viewed head-on), then it’s a Valjoux 7750 chrono movement. If, however, the winding crown sits slightly lower than the chrono pushers either side of it, then it’s the ETA 2892 with the module. Calibre 17 is the Valjoux 7750 chrono movement. Calibre 36 resonates at 36,000 vibrations per hour. The Calibre 360 resonates at a staggering 360,000 vibrations per hour.