The 26470ST is the 42 mm steel Royal Oak Offshore Chronograph. The Offshore, designed by Emmanuel Gueit in 1993, made the Royal Oak larger and more robust: a thicker case, protected crown and pushers and a distinctly sporty character. The 26470ST was made from 2014 to 2021; it succeeded the 26170ST and was succeeded by the 26238ST.
The dial has the coarser Méga Tapisserie pattern and three sub-dials. Calibre 3126/3840 combines an Audemars Piguet self-winding base movement, the 3126, with a chronograph module, the 3840, and has a power reserve of about 50 hours. The watch has a date and is water-resistant to 100 metres. The 26470ST exists with various dial colours, on a steel bracelet or on a rubber or leather strap; the pink gold version is the 26470OR.
On a pre-owned example we test the chronograph, the crown and the pushers, and look at the finishing of the case, where brushed and polished surfaces alternate, at the strap or bracelet and at the set. Because the Offshore is often worn on rubber, we state whether the original strap and clasp are present.