Seiko King Seiko Hi-Beat 5626-5010 (1971)

Presented for auction by Second Vintage This bold King Seiko embodies the height of 1970s Japanese horological design, pairing an ambitious architectural case with one of Seiko’s most celebrated high-frequency calibers. The 56KS family represents a golden era of internal competition at Seiko, where the King Seiko and Grand Seiko factories pushed each other to new heights of precision and finishing. With its distinctive square profile and sharp lines, this timepiece is a striking artifact of vintage Seiko engineering, offering collectors a substantial wrist presence and a historically significant Hi-Beat movement. Brand: Seiko Model: King Seiko Reference Number: 5626-5010 Serial Number: 192943 Movement: Automatic, Caliber 5626 Dial: Silver sunburst with applied indices, showing authentic aging, minor spotting, and oxidation on the hands Case Size: 35 mm (excluding the crown) Case Material: Stainless Steel Production Year: 1971 Condition: Good vintage condition with honest wear and visible patina Dial and Hands The dial features a striking silver sunburst finish that catches the light beautifully, complemented by applied rectangular indices with black central inserts. The applied "SEIKO" and "KS" logos add excellent depth to the upper and lower halves of the dial, while a framed day-date aperture sits cleanly at the three o'clock position. Upon close inspection, the dial exhibits a gentle, age-consistent patina, with scattered light spotting visible across the surface. The sword-style hands retain their original black center stripes but show noticeable surface oxidation and aging, confirming the watch's unpolished vintage authenticity. The dial is signed "JAPAN 5626 - 5020T" along the bottom edge, framing the Suwa factory symbol. Case and Crystal The distinctive square stainless steel case is a testament to the bold design language of the early 1970s. It features heavy vertical brushing on the broad front fascia, which transitions sharply into polished case flanks. The case retains strong overall geometry and factory lines, displaying honest surface scratches and minor handling marks consistent with normal vintage wear over the decades. The flat crystal sits slightly proud of the case and remains clear, offering an unobstructed view of the dial while showing only minor surface wear. The solid stainless steel caseback is exceptionally well-preserved, featuring crisp, deep engravings including the KS logo, the Suwa symbol, the reference number 5626-5010, and the serial number 192943. Movement Powering this timepiece is the highly regarded Seiko Caliber 5626, an automatic Hi-Beat movement renowned for its robust architecture and smooth sweeping seconds hand. Running in vintage operational condition. Maintains the authentic mechanical character of the era. Timegrapher testing indicates a variance of -51 to -60 seconds per day. Strap The watch is fitted with a period-correct black textured leather strap featuring contrasting white stitching. The strap is secured with a standard stainless steel buckle and perfectly complements the robust, angular geometry of the case. Condition This King Seiko is presented in good vintage condition. The case remains thick and well-defined, showing normal, honest signs of wear without appearing over-polished. The dial and hands display visible age-related oxidation and minor spotting, providing a strong vintage character that appeals to purist collectors. The crispness of the caseback engravings further underscores the watch's overall preservation. Dimensions Case Size: 35 mm (excluding the crown) Remarks This reference 5626-5010 is a superb example of 1970s Seiko design, blending an avant-garde square case with chronometer-capable movement architecture. It stands as a highly wearable and historically rich piece for any serious enthusiast of vintage Japanese horology. History The King Seiko line was established in the 1960s as an internal rival to Grand Seiko, a dynamic that drove both divisions to produce some of the finest mechanical watches in Japanese history. The 56KS series, introduced in the late 1960s and flourishing into the 1970s, represented the peak of King Seiko's automated Hi-Beat technology. These models combined high-frequency precision with bold, experimental case designs, perfectly capturing the transition from the conservative mid-century aesthetics to the dynamic, geometric styles that defined the 1970s. / Second Vintage SKU: SEI-SKX-0007