Panerai's innovative approach to watchmaking resulted in it developing military watches for the Italian navy during the early part of the 20th century. It was the trademarked crown-protecting lever bridge that distinguished the first historic Luminor military watch. Additionally, Panerai developed a left-handed model, dsigned to be worn on the right hand by the Italian commandos, who had to wear several instruments on their wrists at once in order to navigate. The new Panerai Luminor 1950 combines the historical elements of its predecessor with contemporary craftsmanship. The special left-handed edition Luminor 1950 3 Day-47mm PAM 557 watch has a vintage-inspired black dial with hour and minute functions, large Arabic numerals and baton markers that are luminescent treated for ultimate visibility after dark. The trademark-protected crown is located at 9 o'clock, providing easy winding of the hand operated mechanical movement. The in-house, Swiss-made calibre P.3000 movement has a three-day power reserve and is water resistant up to 100m. The elegant movement contained within the 47mm stainless steel case is visible through the sapphire caseback and comprises 160 components, 21 jewels and two large bridges holding two spring barrels and gears in place. The large balance wheel provides excellent accuracy with 21,600 oscillations/hr. Among the watch's unique features is the rapid time-changing devise, which enables the hour hand to jump in one-hour increments, leaving the minute hand undisturbed and preserving the watch's accuracy. Presented on an untreated brown alligator leather strap with a stainless steel buckle, the Panerai Luminor 1950 3 Day-47mm PAM 557 watch comes with a second interchangeable rubber strap, a replacement crystal Plexiglas and a steel screwdriver.