Complete set, Hublot, BIG BANG, model: 411.NX.5179.RX, automatic mechanical, satin-polished titanium with 6 H-shaped titanium screws, dial diameter: 45mm Hollowed-out blue dial design: Fully hollowed-out blue movement base plate, hollowed-out Arabic numeral hour markers, highly recognizable; Chronograph sub-dial layout ◦ 3 o 'clock position: 30-minute counter (scale 0-45) ◦ 9 o 'clock position: Small seconds dial Central red tip long second hand: Chronograph second hand Case structure: Signature exposed hexagonal screws, dual chronograph pusher + crown, tough and sporty industrial style; The outer ring of the scale: tachometer scale, with red scale accents, gives a strong sporty visual effect. Hublot's signature flyback chronograph movement can restart the chronograph without resetting to zero, making operation convenient. With a 72-hour ultra-long power reserve, it won't stop even if you don't wear it on weekends. The silicon hairspring is anti-magnetic, and the transparent back cover allows you to admire the skeletonized movement and the blue plate finishing. The vertical clutch timing structure ensures smooth start and stop of timing and stable timekeeping.