Blancpain Fifty Fathoms Ref. 2462 Aqualung US Navy Subase engraved. Although information on these ultimately rare watches is scarce, the use of these watches during military service by some of the most elite armed forces remains a fact. Only a handful of examples of SUBASE (US Naval Submarine Base) have surfaced and each number belongs to a unique watch. The Blancpain Fifty Fathoms and Tudor Submariner have been observed with the same case back engraving and numbered.This example is in nice and genuine condition, the stainless steel case measures 41 mm. The glossy dial pared with the three dimensional bakelite bezel insert place this Blancpain at the top of the golden era of divers watch. The radium markers are unique and specific to the early BP Fifty Fathoms. Overall in good condition, it shows normal signs of wearing.