AUDEMARS PIGUET, PLATINUM 'STAR WHEEL', REF. 25720PT

The “Star Wheel” system was invented by the firm in the early 1990s, including different variations of “wandering hour” wristwatches. Three transparent sapphire disks, or star wheels, each inscribed with four hour indicators are attached to a rotating centre wheel. As the assembly turns, the indicator for the actual hour is rotated into view and then passed across a 120-degree minutes sector. The time is read by noting the visible hour pointing to the current minute. Each disk is obscured until it rises into the arc where the background contrasts the digits into legibility.