Introduction This auction features a distinctive Seiko 5 Actus SS 6106-5440, a remarkable vintage timepiece that captures the bold and geometric design trends of the early 1970s. With its unique square-shaped case and a mesmerizing gradated blue dial, this watch stands as a testament to Seiko's creative peak in mechanical watchmaking. Historical / Era context Produced in the early 1970s—this specific unit dating to March 1973 based on its serial number—the Seiko 5 Actus line was created for the "active" generation of Japanese professionals. The "SS" designation refers to the "Second Setting" (hacking) function, a premium feature at the time. It is powered by the reliable 23-jewel Caliber 6106 automatic movement, a movement celebrated for its durability and precision across Seiko’s mid-century lineup. Condition The watch is running properly. Case: The square stainless steel case shows surface scratches and signs of wear consistent with its vintage age, while retaining its original sharp, boxy geometry. Dial: The gradated blue sunray dial is in very good condition, transitioning beautifully from light to dark blue. The faceted markers and hands remain crisp and legible. Crystal: The hardlex crystal has visible surface scratches and signs of historical wear, as captured in the detailed photographs. Band: The original Seiko-signed stainless steel bracelet is present, showing some typical vintage stretch and surface marks, but remains fully functional. Specifications Brand: SEIKO Model: 5 Actus SS Reference: 6106-5440 Movement: Japanese Automatic (Cal. 6106) Case material: Stainless Steel Case diameter: 34 mm (excluding crown) Dial color: Gradated Blue Band: Original stainless steel bracelet Wrist size: Approximately 17.5 cm Closing note This Seiko 5 Actus SS is a perfect choice for collectors seeking a vintage watch with a strong architectural presence. Its iconic square case and vibrant blue dial make it a versatile and stylish conversation piece. Please examine the high-resolution photos carefully to confirm the condition of this 1970s mechanical classic.