Ordered by the French military in approximately 2000 pieces, the first Type XX chronographs were delivered to the « Centre d’essais en vol » (CEV), the French Air Force and Navy from 1954 to the 1970’s. Known as a flyback chronograph, the Type XX was built specifically for the use of pilots with the function of re-setting and re-starting immediately by simply pressing one button: an invaluable time-saving for pilots at this period. These chronographs had to meet precisely the specifications established by the French army: a black dial with large hands and luminescent Arabic numerals offering good visibilty at night, a 38 mm case with a beautiful dial opening, a rotating bezel, the flyback function, and a pear-shaped crown to facilitate handling with gloves. On the first versions, the Breguet signature did not appear on the dial. On the case back, we can see the guarantee ending dates, attesting to its military origin. The model presented is in very good condition and has a magnificent gilt dial, difficult to find in a similar condition. Today, the Breguet Type XX is one of the most popular « tool watches » for collectors and enthusiasts of fine mechanics. According to Breguet archives, this watch was delivered to the French Air Force on the 17th of June,1955. We would like to thank Emmanuel Breguet and Breguet S.A. for providing us with this information.