MK Personal Collection Unique Rolex Mark IV Double Red Sea-Dweller With Brown Markers, Ref 1665 Wristwatch Circa 1974

MK Personal Collection The present lot is part of a larger privately held collection and is intended for exhibition purposes Unique Rolex Mark IV Double Red Sea-Dweller With Brown Markers, Ref 1665 Wristwatch Circa 1974. This is a very rare model Rolex so called "Sea-Dweller" waterproof up to 2000 feet! The watch has become highly collectible in the secondhand Rolex watch market. This model is 100% correct down to the bracelet. It features a three-body case construction, polished and brushed, first generation helium escape valve at 9, graduated revolving black bezel for the decompression times, “trip lock” winding crown protected by the crown guard, screw-down back and crown Serial # 4.XXX.XXX Ref 1665. It is attached to a steel oyster bracelet #585 / 93150 which is the correct numbers for this series. It has a Cal. 1570, rhodium-plated, “oeil-de-perdrix” decoration Rolex movement with 26 jewels, straight-line lever escapement, monometallic balance adjusted to 5 positions and temperature, shock absorber, self-compensating free-sprung Breguet balance spring with hack mechanism that is in good running condition. It is topped with an original rare exotic Mark IV black dial with unusual deep orange/brown markers (color change dial) and date at 3 o'clock. This is a very rare example of a cool large Rolex sports watch. It is stamped on the inside back cover with serial number inside case as well as the Ref 1665 . The watch is in overall excellent condition. The helium valve, allowing helium and other gases to escape hence enabling the watch to withstand compression even at extreme depths, was developed by Rolex in cooperation with the French diving firm COMEX and used for the Submariner references 5513 and 5514 (see lots 160 and 334 in this auction). Following the success of these models, Rolex decided to commercialize their invention with the launch of the celebrated Sea-Dweller reference 1665 in 1967, the first wristwatch designed for use in saturation diving, fitted with a Rolex patent valve in the band and guaranteed waterproof to 610 meters depth.