Breitling Chronoliner ref. Y24310: 46 mm stainless steel case with black high‑tech ceramic 24‑hour bezel. COSC‑certified Breitling Caliber 24 (ETA/Valjoux 7754 base) automatic chronograph with GMT hand. Sapphire crystal, screw‑down crown, 100 m water resistance. Functions: 12‑hour chronograph, date, red GMT hand (second time zone), rotating 24‑h bezel for a third time zone. Typically supplied on Aero Classic rubber or Pilot bracelet.