The 26240ST is the 41 mm steel Royal Oak Chronograph, introduced in 2022. It was the first steel Royal Oak Chronograph with the integrated in-house calibre 4401, a chronograph movement with column wheel, vertical clutch and flyback function: a single press of the pusher returns the chronograph to zero and restarts it.
The power reserve is about 70 hours, and the movement is visible through the display back. The dial has a Grande Tapisserie pattern, and compared with its predecessor, the 26331ST, the proportions of dial and sub-dials were revised. The watch has a date and is water-resistant to 50 metres. Case and bracelet follow the Royal Oak design, with the octagonal bezel, the eight screws and the integrated bracelet.
On a pre-owned example we test the chronograph completely, including the flyback function, and look at the pushers and crown, at the alternation of brushed and polished surfaces on case and bracelet, and at the completeness of the set. Because the reference is recent, an example may still carry manufacturer's warranty.