This watch is a Seiko Gyro Marvel, one of Seiko’s earliest automatic wristwatches, produced during the late 1950s to 1960s at Suwa Seikosha. The Gyro Marvel occupies a special place in Seiko’s history as an experimental and transitional model. Unlike later mass-produced automatic movements, it employs Seiko’s original “Gyro” winding mechanism, developed in the early phase of automatic watchmaking. This system represents Seiko’s technical exploration before establishing its fully standardized automatic calibers. The dial is signed “Seiko Gyro Marvel” and “Automatic Diashock 17 Jewels”, confirming this as the 17-jewel upgraded version. Originally released with fewer jewels, the Gyro Marvel was quickly refined as Seiko pursued higher durability and performance during intense domestic competition, making the 17-jewel specification a notable evolution. The design reflects late-1950s to early-1960s Japanese watchmaking, with applied hour markers and a clean, understated aesthetic that later influenced Seiko’s higher-grade models. The case shows a well-balanced vintage presence, and the watch is currently fitted with a new leather strap (not original). Condition: The watch has been cleaned and is in good vintage condition. As a vintage timepiece, it shows signs of age and use. Please refer to the photographs for details. When gently shaken, a faint mechanical sound may be heard, which is consistent with the structure of early automatic movements and typical for vintage watches of this era. Function & Disclaimer: The watch was running at the time of listing. However, due to its vintage nature, long-term accuracy, continuous operation, and water resistance are not guaranteed. The watch will be carefully packed and shipped with tracking for safe international delivery.