Notes: The all-gold variation of the Rolex Submariner Date ref. 16618 will appeal to collectors of all lifestyles and professions. Built for optimal waterproofness, the case is equipped with a screw-down case back and a waterproof screw-down crown, allowing it to venture as far as 1,000 feet below sea level. What's more, is the case is topped with a highly visible dial set with lume and a unidirectional bezel that can be adjusted to measure decompression stops and other diving times. A handsome 18 karat yellow gold finish offers a lustrous sheen, creating a statement piece that is appropriate for underwater adventures and formal affairs alike.

Mechanism: The 3135 is a continuation of the 3035 series. Rolex launched it in 1977 and was profoundly different from its predecessors. As the company’s first high-beat movement, it increased the balance speed from 19,800 BPH to 28,800 BPH. This higher frequency has since become the standard across all of Rolex’s range. It also allowed the caliber to provide more accurate timekeeping and better withstand outside influences, such as shock. Like most Rolex mechanisms ending with a "5", this unit has a date function. All modern Rolex date-equipped mechanisms have a 'Quickset' feature as well.

The popular caliber 3135 measures 28.50 mm in diameter and 6.00 mm in height. The Submariner uses this caliber. This makes it quite large when compared with other Rolex movements. The larger size of the movement means that it is more robust and has the ability to incorporate more parts and components. This allows the watch that utilizes it to perform more reliably and durably. It also offers a frequency of 28.800 vph.

Family Notes: The Rolex Oyster Perpetual Submariner is a line of sports watches designed for diving manufactured by Rolex, known for their resistance to water and corrosion. The first Submariner was introduced to the public in 1954 at the Basel Watch Fair. The Rolex Submariner is considered "a classic among wristwatches", manufactured by one of the most widely recognized luxury brands in the world, and due to its popularity has become the subject of massive counterfeiting. The Rolex Submariner is part of Rolex's Oyster Perpetual line. See a copy of the 1957 Submariner magazine advertisement.

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. Rather, both of these early submariners have straight "pencil" style hands. Few, if any, of the 6205 watches bear the name "Submariner" on the dial, a major distinction of modern Submariners. Some 6204 models have the Submariner logo printed below the center pinion, while others have the logo blacked out. It is believed that there were unexpected trademark issues connected with the name "Submariner" at the time the 6204 and 6205 were released, accounting for the inconsistent use of the Submariner mark on these early Submariners. Trademark irregularities notwithstanding, both the 6204 and 6205 are designated Submariner models in Rolex product literature.

From Wikipedia