The Rolex 126660 is new to the Sea-Dweller collection and brings with it a host of modern upgrades. The movement that beats within the case is now the calibre 3235, which boasts a much more efficient skeletonized Chronergy escapement, high-performance Paraflex shock absorbers, a Paramagnetic blue Parachrom hairspring, and a longer 70-hour reserve. The ref. 126660 also includes a stunning blue lume Chromalight display on the Maxi dial, a tougher Cerachrom ceramic bezel insert, a scratch-resistant sapphire crystal without the usually-present Cyclops lens over the date, and a new-style case and bracelet. The case offers a robust 44mm diameter and is equipped with an engraved rehaut, a Triplock screw-down crown, and an innovative Helium Escape Valve. A three-link bracelet accompanies the case and offers a secure hold over both wetsuits and under tight dress sleeves via a Glidelock Oysterlock clasp.