The Submariner model went into production in 1953 and was showcased at the Basel watch fair in 1954. The assigned case reference number of this first Submariner was either 6204 or 6205. It is unclear which model came first; in any event, the two watches are nearly identical. Neither has the distinctive “cathedral” or “Mercedes” hands now so strongly associated with the Submariner line. Throughout the next 40 years, the Submariner was updated with improved water resistance, new movements, and numerous small cosmetic changes. In 2003, Rolex celebrated the Submariner’s 50th anniversary by launching the Rolex Submariner LV anniversary edition (16610 LV), with distinguishing features such as the green bezel and Maxi dial.