Enhancing the Black Bay One with yellow gold creates a version named S&G, for Steel & Gold. TUDOR derived the characteristic aesthetic elements of the Black Bay One S&G model from its history. The overall shape, as well as the domed dial and crystal, c ome from the first TUDOR divers watches. In this version the lines and proportions of the Black Bay One are retained, while the ro t ating bezel and the winding crown are made from yellow gold.