The Blancpain “Fifty Fathoms” was first introduced in 1953, as a tool watch expressly designed for military use. The Fifty Fathoms was designed to meet the needs of French Navy “Frogmen” to support their underwater missions, and was presented as the first purpose-built diving wristwatch. Famous for their highly-functional divers’ timepieces - tool watches are very-much in Blancpain’s DNA. The watch was manufactured by Blancpain, upon request of Commander Maloubier and Lieutenant Riffand of the French navy, following strict technical requirements for a watch fully-reliable and accurate under extreme conditions, found at the ‘Ecole des nageurs de combat’ or ‘Combat Diving School’ of the French Navy. The resulting watch is considered to be the archetypal diver's watch – its name, is derived from the measurement of “50 Fathoms” or approximately 91.45 meters (the greatest depth that a combat diver was allegedly able to withstand at the time).