Hamilton Watch Khaki Aviation Pilot Pioneer H76205530. Inspired by the Model 23, a cutting-edge pocket watch used by U.S. soldiers during WWII, the Khaki Aviation Pilot Pioneer's distinctive design is a tribute to Hamilton's aviation and military heritage. With ultra-legible numerals, cathedral hands and a railway track outer scale, this 38mm automatic pilot watch has a sporty yet refined character that's ready to fly.