Cal. 59360 is an hand winding modular monopusher chronograph movement produced by IWC starting in 2015.

IWC has been transitioning to in-house movements since 2000, enhancing the reputation and technical features of their watches. In 2011, IWC introduced the Cal. 59000 family of hand-wound eight day movements. This family features a single barrel and mainspring and ticks at a modern 4 Hz, making the long 192 hour power reserve extremely impressive.

Cal. 59360, introduced in 2015 in the IWC Portofino Hand-Wound Monopusher, is the only member of this family with a chronograph complication. The movement had been revealed in 2013 at SIHH but was withdrawn before sale and reappeared two years later on a special edition Unique Portofino Hand-Wound Monopusher Edition "Tribeca Film Festival 2015".

Although IWC's contemporary Cal. 89000 family of chronographs was introduced just a few years before, it is a compact, conventional automatic movement with twin pushers. For the Portofino, IWC wanted a classic monopusher design in a large movement befitting the massive diameter of the Portofino case. The chronograph is implemented as a module on Cal. 59215 and features a column wheel yet is only 1 mm thicker than the base movement.

The chronograph mechanism in Cal. 59360 is quite unusual in design. It features a rocking pinion to engage the seconds wheel in the base movement rather than the vertical clutch found on many other high-end chronographs. Another classic and important element is the sautoir, which allows the chronograph minutes hand to jump instantaneously rather than advance continually with the seconds hand.

• Main Article: IWC 59000

• Inside the IWC Cal. 59360 Hand-Wound Monopusher Chronograph, Revolution Watch
• IWC Introduces The Unique Portofino Monopusher Edition "Tribeca Film Festival 2015", SJX