IWC caliber 82665

82665 description

The IWC-manufactured calibre 82665 is an automatic movement that serves as the base for the new Perpetual Calendar IWC-ProSet system, integrating the calendar module into a movement architecture built around ease of adjustment and long-term mechanical precision. Beating at 28,800 vibrations per hour and offering a power reserve of 60 hours, it displays the date, day, month, four-digit year, perpetual moon phase for both hemispheres, and small hacking seconds, while preserving automatic winding through IWC’s Pellaton system.

What distinguishes calibre 82665 is the way the perpetual calendar has been reengineered. Unlike earlier systems built around one-directional correction logic, the IWC-ProSet mechanism is fully synchronised and entirely gear-based, allowing the calendar to be adjusted both forward and backward through a single crown position. Internally, the system relies on multiple functional layers together with flexible, extendable, and retractable fingers, enabling precise daily-step correction without separate corrector buttons or sequential setting procedures. This construction was developed from the ground up around bi-directional usability, while keeping the familiar perpetual calendar display layout intact.

The calibre also incorporates a recalculated moon phase reduction gear, improving the display’s accuracy to a deviation of one day in 1,040 years. Each night around midnight, the synchronised switching sequence advances the date, weekday, and moon phase together; at the end of a month, the month jumps forward, and after twelve months the four-digit year advances accordingly. The month-length and leap-year logic is governed mechanically through a layered programme wheel and month-length wheel, with their complex geometries produced using the LIGA process, which allows highly precise micro-structured components with multiple functional levels integrated into a single part.

From a movement-construction perspective, calibre 82665 combines this new perpetual calendar module with a nickel-phosphorus escapement and a silicon hairspring. The Pellaton winding system winds the mainspring in both directions of rotor motion, while highly stressed winding components such as the automatic wheel and clicks are manufactured from zirconium oxide ceramic to reduce wear. The movement is finished with circular graining and Geneva stripes and is intended to be visible through a sapphire case back.