Rolex "Oyster Perpetual Submariner 660ft/200m", Case No. 1775672, Ref. 5513, Cal. 1520, 39 mm, circa 1968

A diver's automatic wristwatch with centre seconds
Case: steel, screw back ref. 5513 IV/67, reeded turnable bezel, screwed Rolex winding crown, steel "Oyster" fliplock bracelet ref. 93150. Dial: black, luminous indexes, luminous Mercedes hands. Movm.: rotorwind movement, Glucydur balance.

Reference 5513 was fist launched in 1962; it was designed to withstand pressure up to 200 meters (660ft) and featured an 8 mm crown with crown guards. The bezel had minute divisions for the first fifteen minutes and a silver triangle. The face of the watch was black. From 1964 on the inscription "Swiss T<25" was added to the bottom of the dial.