Rolex Watch Datejust 31mm Oystersteel Domed Bezel, Bright Blue Roman Dial, Jubilee Bracelet 278240-0018Specifications: Brand Rolex Model Datejust 31 Reference Number 278240 0018 Case Type Oyster, 31 mm, Oystersteel Case Diameter 31 mm Case Material Oystersteel Bezel Domed Oyster Architecture Monobloc middle case, screw down case back and winding crown Winding Crown Screw down, Twinlock double waterproofness system Crystal Scratch resistant sapphire, Cyclops lens over the date Water Resistance Waterproof to 100 metres 330 feet Movement Type Perpetual,