Reference 3525 was launched in 1939. An important breakthrough model for the firm, the model featured one of Rolex’s most important technological advancements: it was Rolex's very first chronograph wristwatch to be housed in an Oyster case equipped with screw-down caseback along with screw-down crown. This is an important step on the way to the “true” Oyster case (back, crown and pushers all screw-down) which will be introduced to Rolex chronographs with Daytona ref. 6240 in 1965.

Displaying crisp and sharp lines, this reference 3525 is fitted with a black lacquer dial preserved in lovely condition. While over time most Rolex glossy dials loose their shine, in this case it is still remarkably present for a watch 80 years old. Furthermore, tiny oxidation spots that blossomed around the numerals and subcenters create a sort of halo around these details which is as uncommon as it is pleasant.
Compounding to its appeal, the present watch was retailed by hallowed Zurich retailer Beyer, as proudly displayed on the dial. Furthermore, the clasp displays a hand engraved inventory number, and another number is also visible beneath the lug.

The model is affectionately called "Barilotto" by italian collectors (little barrel) given that the narrow lugs impart to the case a markedly “tonneau” vibe. With the case number and reference number well preserved on the outside caseback, it is obvious that the piece was subject only to sympathetic polishing over the years - otherwise these sensitive details would have been lost.

This watch most interestingly displays very similar design specifications to the reference 3525 "Prisoner of War" watches that Rolex supplied to detained British army officers in WWII German war camps. These watches were often fitted with a black dial, gold graphics and luminous hands.