Heuer Sternzeit Reguliert Bundeswehr Chronograph 1551 SGSZ

The Watch . The Heuer Sternzeit Reguliert is a highly specialized, historically significant military chronograph issued to the German Federal Armed Forces (Bundeswehr) for one year only in 1968. Based closely on the standard-issue reference 1550SG, this remarkably rare timepiece was purpose-built for the artillery and rocket corps. Its defining feature is a modified mechanical movement adjusted to track sidereal time—star time—rather than standard solar time. Because the Earth completes a rotation relative to the stars roughly four minutes faster than it does relative to the sun, the movement beats at a slightly accelerated rate. To prevent soldiers from confusing it with standard timepieces during field operations, the watch explicitly bears the bold text "Sternzeit Reguliert" directly on its matte black dial. In the field, the chronograph served as a critical mathematical instrument rather than a simple daily watch. Tied to the deployment of long-range weaponry, it was used in tandem with precision tracking tools like theodolites to determine exact geographic orientations and target coordinates based on the positions of the stars. It is believed that only 50 to 150 of the reference 1551 SGSZ were ever produced for these niche military units, the watch remains an incredibly elusive grail piece, even better this example is accompanied by the Original Bund Folder, paperwork and Sunglasses Case. . The Specs Age: c.1968. Movement: Manual Wind with 30 min Flyback Chronograph. Calibre: Valjoux 230. Timekeeping: Very Good. Service History: Fully Serviced in 2026. Dial: Original Heuer Tritium Dial. Case: Stainless Steel. Measurements: 42mm. Bezel: Bi-Directional. Water Resistant?: No. Hands: Original. Crystal: Original. Crown: Original Unsigned Crown and Pushers. Strap/Bracelet: On a new 20mm Accurate Form Black Leather Strap. Lug Width: 20mm Getting Acquainted . Bits that stand out: - Very rare example. - In superb, all original condition. - Flyback Chronograph Function. - Accompanied by Bund Folder. Nitty Gritty: - None. . Overall this Bund is in Super Vintage condition. The Dial is in very good condition. The Case and the caseback have some minor scratches. Crystal is Original and in excellent condition. Crown and Pushers are Original. The hands are in very good nick. . Photographed on a 7 inch Wrist.