{"product_id":"vintage-1965-japan-seiko-seikomatic-r-slimdate-8305-1010-30jewels-automatic","title":"Vintage 1965 JAPAN SEIKO SEIKOMATIC-R SLIMDATE 8305-1010 30Jewels Automatic.","description":"\u003cbr\u003e\u003ch3 style=\"font-size: 32px; color : #2B0000; margin-bottom: 36px;\"\u003eVintage 1965 JAPAN SEIKO SEIKOMATIC-R SLIMDATE 8305-1010 30Jewels Automatic.\u003c\/h3\u003e\u003cp\u003eWelcome to my auction!\u003cbr\u003eI am Japanese who live in Tokyo.\u003c\/p\u003e\n\u003ch4 style=\"font-size: 24px; color : #2B0000; margin-bottom: 18px;\"\u003eItem description\u003c\/h4\u003e\u003cdiv style=\"font-size: 24px; color:red; margin: 0 50px 18px 35px;\"\u003e\nIt's a SEIKO Automatic Watch, \u003cb\u003eSEIKOMATIC-R SLIMDATE 8305-1010 30Jewels \u003c\/b\u003e.\u003cbr\u003e\n\u003cb\u003eIt's in good used condition.\u003c\/b\u003e\u003cbr\u003e\nIt's difficult to find this valuable watch in such a good condition.\nHighly recommended for SEIKO collectors!\n\u003c\/div\u003e\n\u003cdl style=\"margin:0 0 34px 90px\"\u003e\n\u003cdt\u003e\u003cfont color=\"#970000\"\u003e\u003cb\u003eMovement : \u003c\/b\u003e\u003c\/font\u003e\u003c\/dt\u003e\n\u003cdd\u003e\u003cul\u003e\n\u003cli\u003ePet name : 83 SEIKOMATIC-R CALENDAR .\u003c\/li\u003e\n\u003cli\u003eCaliber number : 8305B.\u003c\/li\u003e\n\u003cli\u003eMovement : Automatic.\u003c\/li\u003e\n\u003cli\u003eBeat rate : 18000bph.\u003c\/li\u003e\n\u003cli\u003eYear of manufacture start : 1963's.\u003c\/li\u003e\n\u003cli\u003eFactory : Suwa.\u003c\/li\u003e\n\u003c\/ul\u003e\u003c\/dd\u003e\n\u003cdt\u003e\u003cfont color=\"#970000\"\u003e\u003cb\u003eExternals : \u003c\/b\u003e\u003c\/font\u003e\u003c\/dt\u003e\n\u003cdd\u003e\u003cul\u003e\n\u003cli\u003eSerial number : 5N31444.\u003c\/li\u003e\n\u003cli\u003eDial number : JAPAN 8305-1020TAD.\u003c\/li\u003e\n\u003cli\u003eGlass : Acrylic.\u003c\/li\u003e\n\u003cli\u003eCase size : About 38.08mm.\u003c\/li\u003e\n\u003cli\u003eLug width : 20mm.\u003c\/li\u003e\n\u003cli\u003eBand : New Leather Strap of SEIKO original.\u003c\/li\u003e\n\u003c\/ul\u003e\u003c\/dd\u003e\n\u003cdt\u003e\u003cfont color=\"#970000\"\u003e\u003cb\u003eCondition : \u003c\/b\u003e\u003c\/font\u003e\u003c\/dt\u003e\n\u003cdd\u003e\u003cul\u003e\n\u003cli\u003eUsed, it runs well.\u003c\/li\u003e\n\u003cli\u003eQuick set(Day\/Date) : Okay.\u003cbr\u003eSet of the date : The set at one stage pulling the crown.\u003c\/li\u003e\n\u003cli\u003eThe day difference time of an used watch is about +-1 minute \/ day.\u003c\/li\u003e\n\u003cli\u003eFor practical, everyday use, it would be advisable to have the movement cleaned and oiled.\u003c\/li\u003e\n\u003c\/ul\u003e\u003c\/dd\u003e\n\u003cdt\u003e\u003cfont color=\"#970000\"\u003e\u003cb\u003eKey Features\u003c\/b\u003e\u003c\/font\u003e\u003c\/dt\u003e\n\u003cdd\u003e\n\u003cli\u003e\n\u003cb\u003eThe Milestone of Mid-60s \"\"Slim\"\" Corporate Luxury (1965):\u003c\/b\u003e In **1965**, the **Seiko Seikomatic-R Slimdate** stood as a highly sophisticated lifestyle statement for Japan's emerging class of young executives and white-collar professionals. The reference **8305-1010** was produced by the **Suwa Seikosha** factory during a landmark historical period when Japanese industry was pivoting toward sleeker, ultra-low-profile architecture. Designed specifically to target the \"\"Business-A\"\" market, it countered the heavy, chunky automatic watches of the early 60s by delivering an incredibly thin, sharp daily instrument that radiated metropolitan confidence and technical pride.\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eThe Advanced 30-Jewel Caliber 8305 Ultra-Thin Heart:\u003c\/b\u003e This watch is powered by the magnificent **30-jewel Caliber 8305** (specifically Cal. 8305C), a high-grade automatic movement operating at **18,000 vibrations per hour (vph)**. In **1965**, a **30-jewel count** was a definitive hallmark of luxury engineering, utilizing extra synthetic rubies to secure the calendar and automatic gear trains. Breaking away from Seiko's traditional Magic Lever system, Suwa engineers developed a specialized **roller-bearing gear-driven winding assembly**, which successfully shaved over 1 mm off the movement's thickness to pioneer a whole new era of mechanical slimness.\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eArchitectural \"\"1010\"\" Oversized Contemporary Case Geometry:\u003c\/b\u003e The reference **8305-1010** is highly celebrated among vintage purists for its distinctively modern, forward-thinking proportions. To compensate for the widened profile of the flattened 83-series movement, Seiko expanded the stainless steel case to a commanding **38mm diameter with 20mm lugs**—an exceptionally bold and contemporary dimension for **1965**. Featuring sharp, elegant lugs and a polished low-profile bezel, the case sits perfectly flat and flush on the wrist, sliding effortlessly under a tailored bespoke suit cuff.\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eMasterful \"\"Slimdate\"\" Visual Symmetry and Reflection:\u003c\/b\u003e The dial of the **8205-1010** is a study in clinical mid-century luxury, showcasing a radiant, rhodium-plated silver sunburst finish. By omitting the day window and focusing entirely on a clean **\"\"Slimdate\"\" configuration at 3 o'clock**, the watch achieves breathtaking visual balance. This canvas is paired with **hand-applied, multifaceted elongated baton indices** and sharp hands that create an elegant play of light. The cursive, printed **\"\"Seikomatic-R\"\" logo** above 6 o'clock remains a prestigious badge of industrial craftsmanship.\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eA Landmark of Suwa's High-Jewel Automatic Legacy:\u003c\/b\u003e Produced in the milestone year of **1965**, the 8305-1010 remains a highly coveted \"\"connoisseur's grail\"\" for vintage collectors who value the evolutionary history of the Seikomatic family. It represents the perfect historical intersection where rugged daily utility met the peak of 1960s minimalist architectural restraint and high-jewel micro-engineering. Originally featuring the iconic **Dolphin or Whirlpool etching** on the case back, it stands as a profound testament to an era when Japan perfected the high-utility executive dress watch for the global stage.\u003c\/li\u003e\n\u003c\/dd\u003e\n\u003c\/dl\u003e\n\u003cdl style=\"margin:0 0 34px 40px\"\u003e\n\u003cdt style=\"font-size: 24px;font-weight: bolder;\"\u003eFor more information, please look at the pictures.\u003c\/dt\u003e\n\u003cdd\u003e\u003cdiv style=\"margin: 14px 0 40px 0;\"\u003e\u003cimg src=\"https:\/\/nonkun.boy.jp\/img_ebay\/1229775175.jpg\"\u003e\u003c\/div\u003e\u003c\/dd\u003e\n\u003cdt style=\"font-size: 24px;font-weight: bolder;\"\u003eNotes\u003c\/dt\u003e\n\u003cdd\u003e\n\u003cul style=\"margin-bottom: 18px;\"\u003e\n\u003cli\u003e\n\u003cb\u003eBefore buying.\u003c\/b\u003e\u003cdiv style=\"padding-left : 30px;\"\u003eThe vintage watches we sell are inspected and adjusted so they work fine. However, since it is an vintage watch, Please purchase on the assumption that it will be repaired.\u003c\/div\u003e\n\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eTo prevent shipping accidents.\u003c\/b\u003e\u003cdiv style=\"padding-left : 30px;\"\u003ePlease monitor the tracking number until the item arrives and if it stagnates, please investigate at your country post office. Also, please confirm the item when you receive the item.\u003c\/div\u003e\n\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eAbout import taxes.\u003c\/b\u003e\u003cdiv style=\"padding-left : 30px;\"\u003eTaxes such as import duties and VAT are not included in the item price or shipping charges, except for items shipped to the US. When you purchase, you will likely be required to pay these fees in your country.\u003c\/div\u003e\n\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eAbout Payment, Shipping, Return.\u003c\/b\u003e\u003cdiv style=\"padding-left : 30px;\"\u003ePayment, Shipping, Return are in accordance with eBay's business policies.\u003c\/div\u003e\n\u003cbr\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/dd\u003e\n\u003c\/dl\u003e\u003cbr\u003e","brand":"Seiko","offers":[{"title":"Default Title","offer_id":52080601923905,"sku":"1229775175","price":88600.0,"currency_code":"JPY","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0995\/8205\/0625\/files\/57_47940491-2ab8-4f84-b4a0-ab2c80628fc6.jpg?v=1786597844","url":"https:\/\/nonkun.com\/products\/vintage-1965-japan-seiko-seikomatic-r-slimdate-8305-1010-30jewels-automatic","provider":"NONKUN Japan","version":"1.0","type":"link"}