The Rolex Deep Sea Sea-Dweller model with the reference number 116660 have been COSC tested. The case is constructed from high quality stainless steel with the Rolex patented Ring Lock System and a titanium case back. The pre-owned models below have 44mm (approximately 48mm with crown) case size and a thickness of about 18mm, the Deep Sea weighs in at 215g grams – as well as having an incredible depth rating of 3,900 meters (12,800 feet). The pre-owned watch models are supplied with a year warranty, equipped with a helium escape valve and a screw-down crown.