NEW VIDEO
IWC Explains Why the Spare Century Slider on Its Perpetual Calendar Repeats "22"
An IWC Replies episode clarifies an engraving oddity and a smart servicing decision.
In a new IWC Replies episode, watchmaker Sabrina Herzog answers a viewer’s question about the century slider. The fitted slider reads 20, 21, 22, keeping the calendar accurate until 2299. The included spare reads 22, 23, 24, extending accuracy to 2499 after installation by a watchmaker.
The repeated 22 is intentional. A slider starting at 23 would leave the display wrong from the first day of 2300 unless swapped at that exact New Year. The overlap gives owners a full century to schedule the swap.
No caliber, no references, nothing on service intervals or requesting the part early.
Source: announcement
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