Introduced in 1988, the Rolex reference 16520 marked a significant milestone in the history of the Daytona. It represented a departure from Rolex's tradition of using Valjoux manual movements, as they introduced the modified Zenith-based caliber 4030. The case was also increased to a modern 40mm size, and it was the first Daytona model to feature a sapphire crystal.

The Rolex reference 16520 with an "L" serial is a rare specimen from the early series of Zenith Daytonas. The first half of the "L" series is characterized by a 4-Liner dial and a bezel insert marked for 200 units per hour. However, in the later production of the "L" series, the watch features an updated 5-Liner dial and is fitted with a bezel insert marked for 400 units per hour.

This particular example belongs to the later series with five lines of text at the 12 o'clock position and serifs on the subsidiary dials. The 12-hour register features a highly sought-after "inverted 6" configuration. The bracelet is an early version without polished center links, which is correct for the period. The subsidiary dials have aged gracefully to a charming yellowish light brown tone, which complements the black dial. The combination of its unique features and rarity makes this 16520 a highly popular timepiece among collectors.