Tudor Black Bay 54 "Lagoon Blue" Watch, 37mm Blue Dial, M79000-0001The Black Bay 54 is the most true to form example of TUDORs first dive watch, the reference 7922. The 37mm case retains the classic proportions of yesteryear yet boasts the technical prowess of TUDORs time only Manufacture Calibre MT5400 and a 200m depth rating. A special version dubbed Lagoon Blue is inspired by the colour of tropical oceans and features a sand textured Lagoon Blue dial, a five link bracelet and a mirror polished bezel.