I f a car has a bumper, then a watch has a bezel. Located on the top and outer edge of a watch, its primary function is to protect the sapphire crystal glass and inner mechanics from the daily bumps and knocks that inevitably beset your timepiece.
Clipped into place or sometimes screwed, the latter method has lent watches such as the sturdy Cartier Santos a tooled, industrial bent. Other design and material features abound, such as gem-set or ceramic bezels which are particularly tough and scratch proof; but a bezel can also add additional functionality to a watch without the need to tinker with the movement.
No diving watch is complete without a unidirectional bezel – line up the large luminous arrow on the bezel with the watch’s minute hand and the dive duration can be accurately timed (if the bezel is knocked accidentally the unidirectional function will only mean that the dive is shortened).
Other bezel functions include the now infamous Rolex GMT (affectionately nicknamed the Pepsi bezel due to its red and blue palette) introduced in the 1950s for the transatlantic pilots of Pan Am. By lining up the extra 24-hour hand with the appropriate hour on the rotating bezel a second time-zone could be read. Robust, protective and functional, the bezel is the un-sung hero of horology.