This Citizen Crystal Seven, reference ACST2908 a-Y, is a beautifully preserved automatic wristwatch that represents the peak of Citizen’s mechanical watchmaking in the late 1960s. Based on the serial number, this watch is considered to have been manufactured around 1967, a period often regarded as the golden age of Japanese mechanical watches. During this era, Citizen was competing at the highest level, producing robust, precise, and well-finished automatic movements designed for long-term daily use. The Crystal Seven line was positioned as a premium automatic series, emphasizing durability, reliability, and refined design rather than excess ornamentation. This model is equipped with a 23-jewel in-house automatic movement and a day-date display, reflecting Citizen’s commitment to practical engineering and mechanical quality. At the time of listing, the watch is running. The silver dial is clean and well preserved, with a balanced layout and applied indices that offer excellent legibility. The red “SUN” day display adds a subtle but distinctive accent, while the overall dial design conveys a calm and confident presence typical of Citizen watches from the late 1960s. The case features a gold-tone bezel marked T.G.P, giving the watch an elegant contrast without appearing overly flashy. With a case diameter of approximately 36.8 mm, as shown in the photographs, the proportions feel well balanced and very wearable even by modern standards. The date can be adjusted via the crown at the first position. The day can be adjusted by rotating the hands. The day display is in English. A new leather strap is currently installed, enhancing comfort and wearability while maintaining a classic appearance. Overall, this watch stands out as a particularly well-preserved example, retaining a clean dial, sharp details, and a strong visual presence that clearly reflects the quality of its era. As a vintage item, the watch was running at the time of listing; however, stable continuous operation and time accuracy are not guaranteed. The watch will be carefully packed and shipped with tracking for safe delivery.