A seldom-seen piece of British military horological history — this is a rare prototype-era CWC RAF-issued 6BB chronograph dating back to the 1970s, produced during the formative years of the Cabot Watch Company after its establishment in 1972. (Cabot Watch Company) Built to Ministry of Defence specification for Royal Air Force personnel, the 6BB chronographs formed part of the legendary “Fab Four” military chronographs alongside Hamilton, Precista, and Newmark. These watches were purpose-built instruments intended for fast jet pilots, navigators, and operational crews rather than commercial sale, making surviving honest examples increasingly scarce today. (CWC Addict) This particular example stands out for its beautifully aged original tritium lume, having developed a rich pumpkin patina across the dial and hands — the kind of warm, even ageing collectors actively search for but rarely encounter in untouched condition. The contrast between the matte military dial and deep caramel lume gives the watch an unmistakably vintage character that modern reissues simply cannot replicate. Housed in the iconic asymmetric steel case and powered by the venerable manual-wind Valjoux 7733 chronograph movement, the watch embodies the utilitarian philosophy of 1970s British military equipment: robust, legible, and entirely purpose-driven. Fixed spring bars, military engravings, and broad arrow markings further reinforce its authenticity as a true issued tool watch rather than a civilian homage. (CWC Addict) Prototype and transitional CWC military pieces from this era are exceptionally difficult to source today, especially examples retaining original military character and attractive untouched patina. With growing appreciation for vintage issued military watches and the historical significance of early CWC production, these RAF chronographs have become increasingly sought after among serious collectors of British military horology. A raw and honest survivor from the golden era of mechanical military chronographs.