This vintage Rolex Sea-Dweller Double Red Ref. 1665 MK4 is a highly sought-after collector’s piece, known for its bold character and historical significance. Featuring the iconic “Double Red” dial with two lines of red text, this MK4 variant showcases original tritium hour markers with a creamy patina, matching the hands perfectly. The 40mm stainless steel case with domed plexiglass crystal and patented helium escape valve reflects its professional diving heritage. Powered by the automatic Caliber 1575, it offers reliable performance and date function. The MK4 dial is distinguished by open 6s and distinctive font spacing, making it a favorite among connoisseurs. An exceptional example of 1970s Rolex tool-watch design, this Sea-Dweller is more than a timepiece—it's a piece of deep-sea history, blending rugged functionality with iconic vintage style