The present watch is a most charismatic and unusual example of one of the first generation of Panerai wristwatches ever made by the celebrated Florentine house, founded in 1860 by Giovanni Panerai (1825-1897).
In the 1930s and following disappointing tests carried out on watches available at that time, the Royal Italian Navy approached Panerai with the request of designing a watch resistant to extreme conditions while at the same time keeping exact time. The prototype which Panerai submitted to the First Submarine Group Command was called "Radiomir" and passed all tests successfully.
Consequently as of 1938, small series of "Radiomir" watches, reference 3646 such as the present watch, were produced for the Italian Navy. The models were fitted with hand-wound movements and waterproof cases supplied by Rolex, the dials consisted of two discs, a lower one coated with "Radiomir" luminous substance visible through the cut out numerals in the black upper disc, enabling the easy reading in the dark or under water. The large cushion-shaped cases had a diameter of 47 mm, wire lugs and a screw-down crown.
During World War I and II, watches and other instruments made by Panerai were standard-issue tools for Italian Navy frogmen, SLC torpedo riders and commandos, later also for naval forces of other countries such as Egypt. A complete set comprising a diver's watch, compass and depth gauge was called "Trittico" (see lot 225 in this auction).
The present example of reference 3646 stands out by its well-preserved, unmolested condition, featuring a rather lesser known variant of the Panerai dial: whereas the model is commonly known with the typical and bold 12-3-6-9 Arabic numerals, this watch uses thin batons and small circular dots as hour markers. The warm brown tinge, a change of colour sometimes found on black dials of a certain age, increases the fascination of this attractive diver's watch.