Launched in 1967, the Sea-Dweller reference 1665 was the first Rolex wristwatch designed for use in saturation diving. It featured a Rolex patent valve in the band, first developed on the Submariner model, to allow helium and other gases to escape, which would enable the watch to stand compression at deep depths.

Very well preserved, the dial of the present watch belongs to the "Mark 4" series of the Double Red Sea-Dweller, distinguished by the printing on its dial. The "double red" colour is of a light red shade. Upon close inspection the printing appears to be made up of a series of dots, rather than direct brush strokes or application. The two double red lines show different sizes: the second line, "SUBMARINER 2000", is smaller than the first line "SEA-DWELLER".

The white characters of the depth rating on the MK 4 dial are both larger and of a different font than those found on earlier dials. In addition, the number 6 of the depth rating is closed.