The Giant DeepSea, the Rolex DeepSea Challenger replica perpetuates the adventure of the Oyster and the pioneering spirit of innovation that has forged the reputation of Rolex. Beyond a certainly point making a watch super water resistant is about armor. The super-sized Submariner style case is a chunky block of very nice 316L steel being 51.4mm wide and 28.5mm thick. The sapphire crystal alone is 14.3mm thick. It is a tank, made to resist the onslaught of pressure from all side. The watch incorporates the Oyster style caseback.