WC, Da Vinci, model: IW376419, Automatic mechanical, stainless steel 43.1* 51mm Case: Barrel-shaped stainless steel case, double-sided anti-reflective curved sapphire crystal; The exclusive irregular-shaped chronograph buttons on the side of the watch are highly recognizable. Dial function ◦ 12 o 'clock sub-dial: Cumulative dial for timing minutes / hours (0-12 hours timing) ◦ 6 o 'clock sub-dial: Regular small seconds hand with a large date window ◦ Outer ring track scale: Tachometer scale, used for speed measurement The luminous three-dimensional hour markers are clear for reading at night Strap: Black fishskin strap with IWC folding clasp, lugs width 24mm.