Seiko 5 Actus SS 輝心 – Kishin 6106-7590 (1973)

Presented for auction by Second Vintage This exceptional Seiko 5 Actus SS from 1973 is a quintessential example of Japanese design language during the exuberant 1970s. Featuring a mesmerizing faceted "Cut Glass" crystal and a deep petrol blue sunburst dial, this timepiece captures light in a truly unique way. The "SS" designation stands for "Second Setting," highlighting the hacking feature that allowed for precise synchronization, a premium specification for the era. This specific reference represents the high-quality domestic models that set Seiko apart globally, offered here in remarkable preservation. Brand: Seiko Model: 5 Actus SS Reference Number: 6106-7590 Serial Number: 321910 Movement: Automatic Caliber 6106 Dial: Gradient petrol blue sunburst with faceted crystal Case Size: 37 mm (excluding the crown) Case Material: Stainless Steel Production Year: 1973 Condition: Near-mint vintage condition Dial and Hands The dial is a stunning example of Seiko's 70s creativity, featuring a rich petrol blue gradient finish that darkens towards the edges. It is fitted with applied polished block indices that complement the geometric aesthetic. The hands are sharp, polished batons in excellent condition. A framed day-date window sits at the three o'clock position, displaying the day in both Kanji and English. The most striking feature is the original faceted crystal, which remains in superb clarity and creates a prismatic effect across the dial face. "SS" and "23 Jewels" markings are crisp and white. Case and Crystal The stainless steel case features the distinct geometry of the Actus line, with a cushion-style profile and a recessed crown at four o'clock for a streamlined silhouette. The surfacing combines brushed upper sections with polished sides, retaining sharp definition that suggests minimal use over the decades. The case edges are crisp, and the geometry remains factory-correct. The faceted Hardlex crystal is a definitive period detail, adding significant visual depth and character to the watch's profile. Movement Powering this timepiece is the robust Seiko Caliber 6106 automatic movement, featuring 23 jewels. This movement is renowned for its reliability and includes the "SS" hacking function, allowing the second hand to stop when the crown is pulled for precise time setting. It also features a push-crown quickset for the date and day. Timegrapher results show a rate of -46 to -51 seconds per day, which indicates a functioning vintage movement operating within acceptable mechanical parameters for an unserviced vintage timepiece. Strap The watch is fitted with a high-quality black leather strap featuring a crocodile grain pattern and black stitching. It complements the dark tones of the dial and provides a dressy, sophisticated contrast to the steel case. The strap is in excellent, unworn condition and ready for immediate wear. Condition This timepiece is in near-mint condition, presenting exceptionally well for a watch comprising over half a century of history. The dial is flawless with no visible staining or oxidation. The case retains its original finishing with only the faintest handling marks visible upon close inspection. The crystal is clear and free of significant chips or scratches. Dimensions The case measures 37 mm in diameter excluding the crown, offering a classic vintage fit that works well on a variety of wrist sizes. The lug width standard allows for easy strap changes, though the current pairing is aesthetically ideal. Remarks The Seiko 5 Actus series was marketed towards the young, trend-conscious generation of the 1970s, often featuring bolder designs than the standard 5 line. This particular "SS" model with the faceted glass is highly collectible due to its specific Japanese Domestic Market styling and the inclusion of the higher-spec hacking movement. It is a time capsule piece that embodies the funk and precision of 1970s watchmaking. History Introduced in the late 1960s, the 5 Actus line bridged the gap between the standard Seiko 5 and the higher-end Lord Marvel or King Seiko lines. It utilized the 6106 caliber, which was a significant step forward in robust automatic movement design, introducing the "Magic Lever" winding system's efficiency to a hackable platform. These watches were durable, stylish, and technically advanced, helping to cement Seiko's dominance during the quartz crisis era by offering undeniable mechanical value. /Second Vintage SKU: SEI1JPQNVP000