The Audemars Piguet Royal Oak Offshore Diver 15720ST is the 2021 refresh of AP's signature 42mm dive watch, and this navy blue dial example presents the most recognizable color of the relaunched generation. Originally introduced in 2010 as the first dedicated Offshore Diver, the 15720ST series brought a sapphire caseback window, an in-house automatic caliber, and a patented quick-release interchangeable strap system to one of the most distinctive sport-luxury divers in production. The 42mm stainless steel case carries the eight signature hexagonal-head screws of the octagonal Royal Oak bezel and the integrated lug geometry that has defined the model since 1972, with two black ceramic screw-locked crowns at 3 and 10 o'clock controlling the time-setting and the internal rotating diver's bezel. The navy blue Mega Tapisserie dial features applied 18k white gold hour markers and Royal Oak hands with luminescent coating, with the black-and-white internal diver's scale visible through the dial cutaway between 12 and 3 o'clock. Powered by the AP in-house Caliber 4308 self-winding movement, beating at 28,800 vibrations per hour through 234 parts and 32 jewels, delivering a 60-hour power reserve. Water resistant to 300 meters. Affirm financing available at checkout. Pre-owned, with papers.