Rolex Oyster Perpetual Sea Dweller DEEPSEA 116660. Steel 43mm case which is water resistant to 3,900 meters (12,800ft) Automatic Chronometer movement. Black dial with luminous blue hour markers and hands. 60-minute graduated Cerachrom disc Uni-directional rotatable bezel, the numerals and graduations are filled with platinum by a patented Rolex technique. RINGLOCK system which allows the case to withstand 2.98 metric tonnes of water pressure. Steel Oyster bracelet with Double Expansion System, manufactured from solid 904L steel, the bracelet can be adjusted to wear over a dive suit up to 7mm thick, double expansion system with flip lock. Box and papers dated April 2018.