Rolex 3646

A historically paramount military dive watch from WWII. Rolex produced the oversized 47mm cushion case and manual-wind Cal. 618 movement, which were then supplied to Panerai. Panerai installed their highly luminous “Radiomir” sandwich dial and delivered the finished secret instruments to Italian Navy combat swimmers. The 3646 is one of the first true “tool” watches, its purely functional design—large size, legible dial, robust waterproof case—becoming the blueprint for all future Panerai watches and a landmark in horological history.