The decorative stone set in the watch crown.

A small dial used for any of several purposes such as keeping track of elapsed minutes or hours on a chronograph or indicating the date.

The 'engine' of a mechanical watch-a large flat spring made from a piece of metal or composite.

Nivarox is a type of antimagnetic steel alloy that is used in balance springs.

The mechanism which tightens the mainspring in a watch.

The main body of the watch containing the watch movement or main components.

A watch with 2 independent time systems.

Any function other than the indication of hours, minutes and seconds.

A function that provides altitude by responding to changes in barometric pressure, commonly found in pilot watches.

Button that is pressed to work a mechanism.

Anti-magnetic (non-magnetic) watches are those that are able to run with minimal deviation when exposed to a certain magnetic field.

The protective cover at the back of the watch case which can be removed to allow access to the internal watch movements for maintenance.