News · IWC Schaffhausen
IWC's Perpetual Calendar ProSet corrects both ways, first in a Mercedes-Benz Big Pilot
IWC's new Perpetual Calendar ProSet corrects forward or backward from one crown position, and it arrives in a 140-piece Big Pilot for Mercedes-Benz at A$60,300.
Hen & Mills Editorial · 3 min read · 14 August 2026
Overshoot the date on a perpetual calendar and you normally pay for it. Forward through the entire correction, a fortnight of button pushing if you have the patience, a trip to the service centre if you do not. IWC has built one that runs backwards, with four patents holding it together.
It is called the Perpetual Calendar ProSet, and it turns up first in the IW329603, released on 13 August as a 140-piece run marking 140 years of Mercedes-Benz. The module is gears the whole way through, no levers, and every calendar reading corrects forward or backward from a single crown position. No pushers on the case, no hunting for a second or third click, no sequence to memorise. You set the calendar the way you set the time.
Four patents to make a calendar go the other way
A conventional perpetual calendar is a stack of levers and cams that only knows how to move forward. Correcting one is enough of a chore that plenty of owners leave the watch in a drawer to run itself down rather than face it, and I have never found that hard to understand. Getting the whole train to work in both directions is a genuinely difficult problem, and IWC spent four patents on it.
The layout is IWC's full calendar as usual. Date at 3, month at 6, day of the week at 9, and the four-digit year tucked between 7 and 8, which the brand has been doing for decades. The moon phase sits at 12 in the Double Moon style, good to a day out every 1,040 years. I will take their word for that one.
42mm, which is the quiet end of the Big Pilot
The case is brushed and polished stainless steel, 42mm across and 14mm tall, water resistant to 10 bar with a screwed-in crown. That is restrained for a Big Pilot. The family sat at 46mm and up for years, and 42 is the size that finally made the current generation wearable.
Inside is IWC's own calibre 82665, running at 28,800 vibrations an hour with 34 jewels and 280 components. There is a nickel-phosphorus escapement and a silicon hairspring, and the bidirectional Pellaton winding gets ceramic parts, IWC's long-running answer to the wear the Pellaton system used to cop. Power reserve is 60 hours.
The dial is black with golden appliqués and hands, and the minute track is printed in white so you can actually read it. Strap is black rubber on the EasX-CHANGE quick-release, 21mm at the lugs and 18mm at the buckle, off without tools.
The Mercedes-Benz link is under the sapphire caseback
The car connection lives on the back rather than the dial, which is the right call. IWC has used the first Mercedes-Benz logo, the one adopted in 1926 when Daimler Motoren-Gesellschaft merged with Benz & Cie, the laurel wreath from the Benz emblem wrapped around DMG's three-pointed star.
The anniversary goes back further than the logo does. Carl Benz filed the patent for the first automobile 140 years ago, and Gottlieb Daimler built his motorised carriage not long after.
A$60,300 buys you the module, not the metal
The A$60,300 comes from IWC's Australian storefront and includes GST. It is a lot for steel on a rubber strap, and I would not pretend otherwise. What the money is actually for is a perpetual calendar with a genuinely new correction system, from a manufacture that builds its own movements, in a run of 140 tied to a partnership that has been real for years rather than dreamt up for the launch.
IWC has shown one photo so far. If the ProSet works on the wrist the way it reads on paper, it is the most useful thing to happen to a perpetual calendar in a long time, and it will end up in watches costing a great deal less than this one.
