Power reserve indicator

A power reserve indicator shows you how many hours of energy your watch has left. When you wind your watch or swing your automatic watch, your power reserve is recharged and your display increases. As soon as the power reserve display shows 0, your mechanical watch no longer has any energy and it stops. Power reserve indicators are particularly practical for watches with a hand-wound caliber, as they do not wind up when worn. Power reserve displays are usually retrograde displays and are most commonly found on dress watches.