Rolex Sea-dweller 16660 MK1 Matte Dial 1985 with the hidden signature in

with the hidden signature in the X numeral and a date function

Serial 255xxxx dating to 1971

-⁠ ⁠Fully checked by our watchmaker

and softens more and more over time

- Yellow gold case 24 x 30mm

Rolex Sea-dweller 16660 MK1 Matte Dial 1985 with the hidden signature inWith this Sea Dweller, also nicknamed the Triple Six, Rolex doubled the depth rating to 4,000 ft thanks to its larger helium escape valve and sapphire crystal, compared to its predecessor, reference 1665. Furthermore, Rolex introduced a unidirectional bezel for diver safety, making this Sea Dweller a true transitional model. This example features a rare matte dial, used in the first production batch before Rolex later switched to glossy dials with