Presented for auction by Second Vintage This captivating vintage Seiko exemplifies the adventurous and highly geometric design language that defined Japanese watchmaking in the 1970s. Produced by the legendary Daini Seikosha division, this timepiece perfectly balances a sophisticated, traditional dial layout with a robust, avant-garde case architecture. The striking contrast between the deep blue sunburst dial and the sharp, vertically brushed stainless steel case makes this a highly versatile and collectible piece for enthusiasts of golden-era Seiko. Brand: Seiko Model: Automatic Reference Number: 2409-0020 Serial Number: 293333 Movement: Automatic Caliber 2409A, 23 Jewels Dial: Deep blue sunburst dial with painted white Roman numerals, exceptionally clean condition Case Size: 31 mm (excluding the crown) Case Material: Stainless Steel Production Year: September 1972 Condition: Excellent vintage condition, showing sharp factory case lines and a beautifully preserved dial Dial and Hands The watch features a mesmerizing deep blue sunburst dial that plays beautifully with the light, transitioning from vivid cobalt to dark navy depending on the angle. The dial is appointed with crisp, white painted Roman numerals that provide excellent legibility and a refined aesthetic. At the three o'clock position, a framed day-date aperture displays a dual-language English and Kanji day wheel, adding a highly desirable touch of Japanese domestic market heritage. The Daini Seikosha double lightning bolt logo is proudly printed above the six o'clock marker. Silver-tone baton hands sweep across the dial, complementing the overall metallic theme. Crucially, the dial is in exceptionally clean condition, free from notable moisture damage, spotting, or discoloration, presenting a stunning and pristine vintage appearance. Case and Crystal The 31 mm stainless steel case features a distinctive hooded lug, tonneau-style profile that sits with substantial presence on the wrist despite its compact dimensions. The upper surface of the case exhibits heavy, factory-original vertical brushing that contrasts brilliantly with the highly polished case flanks. The transitions between the brushed and polished surfaces remain remarkably crisp and well-defined, indicating careful ownership over the decades. Honest, light surface scratches and minor handling marks are visible upon close inspection, entirely consistent with normal vintage wear. The recessed crown at three o'clock maintains the sleek silhouette of the case. The watch is fitted with a flat crystal featuring a subtly chamfered edge, offering an unobstructed view of the dial while showing only minor, superficial signs of use. Movement Inside the case beats the Seiko caliber 2409A automatic movement, featuring 23 jewels. The movement presents cleanly in the provided macro photographs, with the rotor and bridges displaying standard factory finishing, alongside crisp red Daini Seikosha and caliber engravings. Running in vintage operational condition. Maintains the authentic mechanical character of the era. Timegrapher testing indicates a variance of -55 to -60 seconds per day. Strap The watch is paired with a period-correct black leather strap featuring an alligator-style grain pattern. The strap is finished with contrasting dark stitching and a classic stainless steel pin buckle, perfectly complementing the dressy yet bold nature of the timepiece. Condition This Seiko is presented in excellent vintage condition. The case retains strong, original geometry with beautifully preserved factory brushing on the upper hood. The dial is the standout feature, remaining remarkably well-preserved with no glaring flaws, while the hands and painted indices remain bright and sharp. Normal, light micro-scratches are present on the polished flanks and the screw-down caseback, which are entirely expected and consistent with the age of the watch. Dimensions The stainless steel case measures exactly 31 mm in diameter, excluding the recessed crown. Remarks This Seiko reference 2409-0020 is a fantastic representation of Daini Seikosha's 1970s design ethos. By combining a sophisticated, classic Roman numeral dial with a robust, geometrically intriguing brushed case, Seiko created a watch that feels both elegant and distinctly retro. It is a highly wearable and visually arresting piece for any collector of vintage Japanese horology. History During the 1970s, Seiko's internal rivalry between the Suwa and Daini factories produced some of the most innovative and striking designs in the brand's history. The Daini Seikosha facility, denoted by the distinct lightning bolt logo on the dial, was known for pushing the boundaries of case manufacturing and dial finishing, often heavily influenced by Taro Tanaka's Grammar of Design principles. This specific model perfectly encapsulates that era, offering a blend of traditional dial layouts with the sharp, faceted case architecture that defined the golden age of vintage Seiko production. 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: SEI-SAX-0022