勞力士，精細及罕有，不銹鋼及金自動上弦鏈帶腕錶，配中心秒針及黑色錶盤，型號3536，約1940年製 瑞郎20,000-40,000

Reference 3536 is an exceedingly rare example of an early Oyster Perpetual model, hardly published in literature and scarcely appearing in public. It was introduced into the market in the 1930s and available in stainless steel and pink gold or stainless steel and yellow gold and with different dial layouts.

Reference 3536 is doubtlessly one of the most unusual "bubble back" models ever made and easily distinguishable from the better known versions by its unusual design, featuring a round case, a concave or inward-curved enlarged bezel and slender straight lugs. The highly attractive appearance of this rare wristwatch is topped by the inlay between the lugs, rendering the model its designation "hooded".