The Breitling Superocean 46 A17378 is the current-generation 46mm stainless steel professional diver in the blue ceramic configuration, and the reference that anchors the upper end of Breitling's modern Superocean collection. Originally launched as a redesign of the Superocean line in 2022, the A17378 carries the slimmer profile, more refined ceramic bezel, and updated dial graphics that distinguished the 2022 generation from the prior chunkier Superocean architecture. The 46mm stainless steel case measures 13.22mm thick, with a bidirectional rotating blue ceramic bezel with security lock, a screw-down crown, and 300 meters of water resistance, all protected by a cambered glareproofed sapphire crystal. The blue dial carries broad luminous Arabic numeral hour markers in Super-LumiNova, oversized luminous hands designed for legibility at depth, and the date aperture at 3 o'clock. Powered by the Breitling Caliber 17 self-winding movement, COSC chronometer certified, beating at 28,800 vibrations per hour through 26 jewels with a 38-hour power reserve. The Superocean lineage traces back to 1957, when Breitling introduced the original Superocean as a dedicated tool watch for professional and military divers. Pre-owned.