Bezels not only look chic on watches, they also perform some very special and often important functions.
The bezel is the part of the watch case that surrounds the watch glass. This outer ring is either permanently locked in place, or rotatable. The bezel can either be a bit wider and have different markings, or it can be narrow and unadorned.
The word bezel comes from the French lunette, which means glasses or binoculars. Sometimes imprints on the dial are incorrectly referred to as the inner bezel.
The diving watch
The bezel of the diving watch marks the dive time. Shortly before entering the water, divers marked the current position of the minute hand with the luminous triangle on the rotating bezel so that they know exactly how long they have been diving and how long the oxygen will last. Depending on the model, diving bezels have 60 or 120 clicks, so the immersion time can be set to either a minute or half a minute.
The bezels of diving watches are unidirectional, i.e. they can only be rotated in one direction. This ensures the remaining diving time is only shortened and not extended.
The bezel of a pilot’s watch
The bezel of the pilot’s watch is bidirectional, which means that it can be rotated in both directions. Pilot bezels are still used today by pilots who fly visual flight. Just like with divers’ bezel, the current position of the minute hand is marked as the zero point when starting. During the visual flight, navigation is then carried out using the past minutes, a map, and distinctive features of the landscape.
The chronograph bezel with tachymeter scale
Chronographs have a stopwatch function and usually a fixed bezel with a tachymeter scale. This can be used, for example, to measure the average speed of a vehicle. For this, the time required for one kilometre is stopped. For example, at 20 seconds the average speed is 180 km / h, and at 30 seconds it is 120 km / h. This value can easily be read off.
The countdown bezel
In direct contrast to the count-up bezels found on aviator or diving watches, the minute division on the countdown bezel is counter-clockwise. To use this functionality, simply twist the bezel so that the time remaining until the start of the event aligns with the minute hand. Then, once the minute hand reaches zero, the countdown is complete.
They are often found on military watches which can, for example, monitor the countdown to the launch of a missile.
