The chronograph Audemars Piguet finally built for the case.
For most of its life the Royal Oak chronograph ran on a modified supplied base with a chronograph module on top. Calibre 4401 changed that: an integrated, column-wheel, flyback chronograph developed in house, with around 70 hours of reserve, which is what the 26240 carries.
The practical difference is in the pushers and the dial. An integrated chronograph gives a crisper action at the pusher and lets the counters sit where the designer wants them rather than where a module dictates, which is why the 41 mm case reads cleaner than the generation before it.
Everything else is the 1972 Genta design doing what it has always done: the octagonal bezel with its eight hexagonal screws, the tapisserie dial, and a bracelet that tapers into the case rather than hanging off it. The blue dial in steel is the configuration most people mean when they say Royal Oak chronograph.
- Calibre 4401, an integrated flyback chronograph made in house
- Approximately 70 hours of power reserve
- Blue Grande Tapisserie dial with applied white gold markers
- 41 mm case with the octagonal bezel and eight hexagonal screws