When it was launched in 1971, the Explorer II set new standards for chronometric precision, strength and clarity. Now, the Explorer II has the hallmarks of the ideal instrument to push the boundaries of exploration. A robust 42 mm case in 904L steel with bold numerals on its bezel distinguishes the latest generation. The Explorer II is equipped with calibre 3187, a self winding mechanical movement entirely developed and manufactured by Rolex. This week, we present a black dial version.