Introduced in 1988, the Sea-Dweller 16600 is the heavy-duty brother of the Submariner 16610 of the same era. Compared to the Submariner, its case -now fitted with a helium escape valve- is slightly thicker. The glass does not feature the cyclops. The 16600 was replaced by the Deepsea 116660 in 2008. The watch pictured has a case sans lug holes and as such carries the ref. nr 16600T.