The DRSD models are not only significant for their technological innovation but also for their role in Rolex’s history as a maker of professional dive watches. Their durability, coupled with the unique aesthetic of the red text and the vintage appeal of the domed acrylic crystal, make them a favorite among collectors. The variations in dial markings, case back inscriptions, and the patina developed over time contribute to each piece’s unique story, embodying Rolex’s commitment to excellence and innovation in the world of dive watches. These models have two rows of red writing on the dial, and case backs with “Rolex Patent Oyster Gas Escape Valve” engraving. By this time, the helium escape valve has been successfully patented by Rolex.