This rare, Breitling 1765 Unitime was introduced in the 1960s, as a tool watch expressly designed for pilots, with this example dating to circa 1967, based on its outer-caseback serial number and '765 CP' case.

The earliest AVI references (or 765s), were used by civilian aviators and military Air Forces in the late 1930s. These wristwatches were the first to be launched by the Breitling EIGHT Military aviation division; bearing many of the classic hallmarks typically associated with military pilots wristwatches. The Breitling EIGHT Air Force utilized the latest technical advancements to manufacture highly-specialised equipment, using only materials of the best quality, such as cockpit clocks, oscillographs as well as complicated wristwatches. Post-AVI designation, fewer than 1000 Unitime examples are estimated to have been produced.

The reference 765 AVI predates Breguets famous type XX, introduced in 1954 and issued to the Arme de lAir, Aeronavale and C.E.V (Centre dEssais en Vol C Flight Test Center). The French military used watches by Breguet, Auricoste and Vixa. The Breitling 765 AVI, produced in 1953, was seemingly the influential benchmark used throughout the design process of these later examples, emphasizing legibility, waterproofness, and enhanced reliability.

This example, the Breitling 1765 Unitime, with serial number (127,6XXX) has a round, stainless steel case with large chronograph pushers and an original Breitling, fluted crown. The case measures 41 mm in diameter, denoting it is an earlier example based upon a 765 CP case, rather than the slightly-larger 7650 case. It has thick straight-line lugs with sharp bevels, retaining exceptional definition. Like all 765 examples, the case-back is screw-down, and features sharply preserved engraving; 1765 Unitime, along with WATERPROOF - SHOCK PROTECTED - ANTIMAGNETIC - STAINLESS-STEEL and the manufacturer's signature.

It features a white Breitling logo, while 'Breitling Geneve Unitime' is referenced on the dial at twelve o'clock. Visible at six oclock, below the twelve-hour register, a 'SWISS' marking is replaced on the reference 1765 by the letter T, denoting the Tritium luminescent material on the dial.?The case features a, bi-directional, rotating bezel with twenty four-hour graduation.?

The chronograph, minute and hour hands are white, giving the dial a nice monochromatic look. The sub-registers at three, six and nine o'clock are the thirty-minute, twelve-hour and the sub-second dials, respectively. The minute-recording sub-register features a luminescent arrow hand, ensuring optimal legibility.

The watch carries a manual-winding Venus calibre 178, considered by many as one of the most famous column wheel operated chronograph calibres of all time. The movement features 17 jewels and a modified 24-hour time, beating at 18,000 A/h, with a power reserve of 45-hours. This 'standard' column wheel movement for Breitling Chronographs has a twist; instead of the usual twelve-hour dial, this modified movement has twenty-four hour dial in which the hour hand takes twenty four hours to make a full rotation. The request for the 24-hour modification was first made by US Navy test pilot and astronaut Lt Cmdr Scott Carpenter, who wore a Breitling Navitimer (12-hour version) during the 1950s.

Viewings can be arranged in Central London by appointment only.

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