Presented for auction by Second Vintage A superb example of late-1960s horological innovation, this Longines Ultra-Chron dates to circa 1968 and represents the brand's pioneering work in high-frequency movements. Designed to offer unparalleled accuracy, the Ultra-Chron line remains highly sought after by collectors who appreciate significant mechanical achievements paired with timeless mid-century aesthetics. This particular piece showcases a striking tonneau case and a beautifully preserved silver sunburst dial, capturing the essence of vintage elegance and technical mastery. Brand: Longines Model: Ultra-Chron Reference Number: 7951-2 Serial Number: 14716655 Movement: Automatic, Caliber 431, 17 Jewels Dial: Silver sunburst dial with applied faceted indices, crosshair motif, and applied logos, presenting in excellent, clean condition Case Size: 37 mm (excluding the crown) Case Material: Stainless Steel Production Year: Circa 1968 Condition: Excellent vintage condition with sharp case lines and a highly attractive dial Dial and Hands The striking silver sunburst dial features a delicate crosshair motif and applied faceted block indices with contrasting black accents, providing excellent legibility. The applied Longines winged hourglass and the distinct Ultra-Chron logo add remarkable depth to the dial furniture. The serif and sans-serif typography remains crisp and fully intact, including the "SWISS" designation at six o'clock. A neatly framed date aperture is positioned at three o'clock. The baton hands feature matching black center stripes and present beautifully. Under close visual inspection, the dial remains exceptionally clean, showing only the faintest signs of age-consistent character, completely free from heavy spotting, staining, or moisture damage. Case and Crystal The 37mm stainless steel case exhibits a robust tonneau profile with a beautiful interplay between the brushed upper surfaces and polished flanks. The lug transitions are sharp and well-defined, indicating respectful wear and careful handling over the decades. The original signed crown remains present and functional. The screw-down caseback is clearly stamped internally with the reference 7951-2. The watch is fitted with a domed acrylic crystal that shows some light surface scratches consistent with normal use, which do not detract from the clear view of the dial beneath. Movement Powering this timepiece is the celebrated Longines Caliber 431, a high-frequency automatic movement operating at 36,000 vibrations per hour. The movement is marked with the caliber designation and the serial number 14716655, clearly visible on the pristine rhodium-plated bridges. The rotor and plates exhibit fine finishing and remain visually clean. Performing well within expected vintage tolerances; running strong and steady. Timegrapher results show a deviation of -20s to -29s/day. Strap The watch is presented on an original Longines stainless steel brick-link bracelet that perfectly complements the case geometry. The folding clasp is prominently signed with the applied Longines winged hourglass logo, confirming its authenticity. The bracelet displays normal signs of wear and accommodates a wrist size of up to 18cm. Condition Excellent vintage condition. The case retains strong factory lines with honest, light handling marks. The dial is remarkably well-preserved, and the movement is clean and operational, making this a prime example for collectors. Dimensions Case Size: 37 mm (excluding the crown) Wrist Size: 18 cm Remarks The Longines Ultra-Chron is a historically significant model, celebrated for its high-beat movement. Finding an example from circa 1968 with such a clean dial and sharp case, complete with a signed Longines bracelet, offers a fantastic opportunity for the discerning collector looking to add a piece of horological history to their collection. History Introduced in 1967 to commemorate Longines' centenary, the Ultra-Chron was marketed as the world's most accurate watch, guaranteed to be accurate to within a minute a month. This achievement was made possible by the high-beat Caliber 431 movement. The Ultra-Chron stands as a testament to Longines' historical prowess in precision timekeeping and remains a pivotal model in the brand's storied archive. Payment and Shipping Payment must be completed within 1–3 days after purchase. Your watch will be professionally and very securely packaged, and shipped with tracking and insurance for your peace of mind. We ship via fast express service, with typical delivery in 1–4 business days (destination dependent). Note that with vintage watches, minor signs of wear, aging, or imperfections may be present and are considered normal for watches of this age. Please review all photos carefully before bidding. We strive to photograph each watch from multiple angles for the most accurate representation. The photos form an important part of the description. If there are any concerns of functionality or defects after delivery, make sure to contact us within 3 days of receiving the watch so we can assist you. As with all vintage watches, water resistance is not guaranteed. If you have any questions, feel free to contact us after the auction ends. / Second Vintage SKU: LON-LUX-0002