Cvstos Challenge Chrono II of 76 pieces. This watch has a blue carbon and steel tonneau-shaped case, 53.7mm x 41mm. Open case-back with sapphire crystal. Sapphire crystal face with none-reflecting coating. Water-resistance 100 meters Polished titanium screws with exclusive CVSTOS TECHNOLOGY pattern. Screw-down crown, made from titanium. Dial Arabic numbers. Exclusive CVSTOS TECHNOLOGY decoration. Sapphire, none-reflective coating. Super-Luminova treated indexes. Hands are pierced, chromed and Super-Luminova treated. Automatic chronograph caliber CVSTOS 577. Functions Chronograph, power-reserve indicator, date. (date disc skeletonized). Power-reserve 42 hours Jewels 25 Frequency 28,800 vibrations per hour White Rubber (Nitril-NBR®) strap with buckle Folding clasp.