Portugieser Tourbillon Day & Night

Continuing its legacy in the realm of grand complications, IWC presents the Portugieser Hand-Wound Tourbillon Day & Night (Ref. IW545901) , featuring an 18-karat Armor® gold case, polished and satin-finished, with gold hands and appliqués. Thanks to its enhanced microstructure, Armor® gold is significantly harder and more wear-resistant than traditional 5N gold.

The highly polished obsidian black dial offers remarkable depth and creates a striking visual contrast. The watch is fitted with an elegant curved black alligator leather strap, crafted by Santoni , the renowned Italian manufacturer of luxury shoes and leather accessories.

At 6 o'clock is a minute-by-minute flying tourbillon , one of the most sophisticated complications in haute horlogerie. The assembly and adjustment of this delicate mechanism are reserved for IWC Schaffhausen's most experienced master watchmakers. The tourbillon places the balance wheel and pallet fork in a rotating cage that completes a full rotation on its axis every minute. This constant rotation compensates for the effects of gravity on the oscillating system, thus improving the watch's accuracy.

Because the tourbillon cage is stopped and restarted several times per second, its overall weight must remain extremely low. Although composed of 56 components , the mechanism weighs only 0.675 grams . The anchor and escape wheel are made of silicon and treated with a special diamond coating known as Diamond Shell® . This technology reduces friction and improves energy transmission within the movement, contributing to a high power reserve of 84 hours .

Thanks to the integrated stop-tourbillon mechanism, it is possible to completely stop the movement and set the watch to the nearest second .