{"product_id":"serviced-vintage-1965-japan-seiko-seikomatic-r-8305-0020-30jewels-automatic-1","title":"Serviced Vintage 1965 JAPAN SEIKO SEIKOMATIC-R 8305-0020 30Jewels Automatic.","description":"\u003cdiv style=\"display: none;\"\u003e\n\u003ch1\u003eServiced Vintage 1965 JAPAN SEIKO SEIKOMATIC-R 8305-0020 30Jewels Automatic.\u003c\/h1\u003e\nServiced Vintage 1965 JAPAN SEIKO SEIKOMATIC-R 8305-0020 30Jewels Automatic.Welcome to my auction!I am Japanese who live in Tokyo. Item description It's a SEIKO Automatic Watch, SEIKOMATIC-R 8305-0020 30Jewels . It's in good used condition. It's difficult to find this valuable watch in such a good condition. Highly recommended for SEIKO collectors! Movement : Pet name : 83 SEIKOMATIC-R.Caliber number : 8305C.Movement : Automatic.Beat rate : 18000bph.Year of manufacture start : 1965's.Factory : Suwa.Externals : Serial number : 5309108.Dial number : JAPAN 8305-0011TAD.Glass : Acrylic.Case size : About 37.8mm.Lug width : 19mm.Band : New Leather Strap.Condition : Used, it runs well.Quick set(Day\/Date) : Okay. Set of the date : The set at one stage pulling the crown.The day difference time of an used watch is about +-1 minute \/ day.Overhaul service in April 2026.The movement has been cleaned and oiled, so it works fine.Key Features The Dawn of Refined Slim Automatics (1965): In **1965**, the **Seikomatic-R** series was introduced as a sophisticated upgrade to the standard Seikomatic line. The reference **8305-0020** was produced by the **Suwa Seikosha** factory to meet the demands of high-ranking professionals who sought a more elegant, \"\"Refined\"\" timepiece. It arrived during a landmark year for Seiko, bridging the gap between practical business watches and elite luxury models like the King Seiko, symbolizing the quiet confidence of Japan's mid-60s economic leaders. The High-Grade 30-Jewel Caliber 8305 Heart: This watch is powered by the **30-jewel Caliber 8305**, a premium automatic movement operating at **18,000 vibrations per hour (vph)**. In **1965**, a **30-jewel count** was an extraordinary mark of mechanical prestige. These synthetic rubies were strategically placed to minimize friction in the slender gear train and the high-efficiency winding system. This movement is celebrated for its remarkably thin profile, achieving a \"\"dress watch\"\" silhouette without sacrificing the convenience of automatic winding. Architectural \"\"0020\"\" Modernist Case: The reference **8305-0020** features a sturdy yet slender stainless steel case with long, elegant lugs that follow the wrist's contour. A signature trait of this era is the **recessed crown at the 4 o'clock position**, which sits nearly flush with the case side. In **1965**, this design was a visual manifesto of Suwa Seikosha's engineering pride—communicating that the self-winding mechanism was so efficient that manual adjustment was rarely needed, resulting in a clean, aerodynamic profile. Masterful \"\"Self-Data\"\" Dial Purity: The dial of the **8305-0020** is a study in minimalist luxury, featuring a radiant sunburst silver finish and **hand-applied, multifaceted baton indices**. By focusing on the \"\"Self-Data\"\" (date only) complication at 3 o'clock, Seiko achieved a perfectly balanced and uncluttered layout. The applied **\"\"Seikomatic-R\"\" script** and the Suwa factory symbol remain prestigious hallmarks, emphasizing a professional aesthetic that prioritized clarity and timeless Swiss-rivaling elegance. A Landmark of Suwa's \"\"Slender-Matic\"\" Legacy: Produced in **1965**, the 8305-0020 remains a highly coveted reference for collectors of the \"\"Golden Era\"\" of Seiko automatics. It represents the perfect intersection of **mechanical complexity and the \"\"thin-is-luxury\"\" design philosophy** of the 1960s. It stands as a testament to an era when Suwa Seikosha perfected the **\"\"High-Jewel, Low-Profile\"\" automatic**, creating a reliable and dignified masterpiece that remains as stylish today as it was over half a century ago. For more information, please look at the pictures. Notes Before buying.The 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. To prevent shipping accidents.Please 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. About import taxes.Taxes 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. About Payment, Shipping, Return.Payment, Shipping, Return are in accordance with eBay's business policies. \u003c\/div\u003e\n\n\n\u003cbr\u003e\u003ch3 style=\"font-size: 32px; color : #2B0000; margin-bottom: 36px;\"\u003eServiced Vintage 1965 JAPAN SEIKO SEIKOMATIC-R 8305-0020 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 8305-0020 30Jewels \u003c\/b\u003e.\u003cbr\u003e\n\u003cb\u003eIt's in good uséd 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.\u003c\/li\u003e\n\u003cli\u003eCaliber number : 8305C.\u003c\/li\u003e\n\u003cli\u003eMovement : Automatic.\u003c\/li\u003e\n\u003cli\u003eBeat rate : 18000bph.\u003c\/li\u003e\n\u003cli\u003eYear of manufacture start : 1965'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 : 5309108.\u003c\/li\u003e\n\u003cli\u003eDial number : JAPAN 8305-0011TAD.\u003c\/li\u003e\n\u003cli\u003eGlass : Acrylic.\u003c\/li\u003e\n\u003cli\u003eCase size : About 37.8mm.\u003c\/li\u003e\n\u003cli\u003eLug width : 19mm.\u003c\/li\u003e\n\u003cli\u003eBand : New Leather Strap.\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\u003eUséd, it runs well.\u003c\/li\u003e\n\u003cli\u003eQuick set(Day\/Date) : Okay. Set of the date : The set at one stage pulling the crown.\u003c\/li\u003e\n\u003cli\u003eThe day difference time of an uséd watch is about +-1 minute \/ day.\u003c\/li\u003e\n\u003cli\u003e\u003cb style=\"color : red\"\u003eOverhaul service in April  2026.\u003cbr\u003eThe movement has been cleaned and oiled, so it works fine.\u003c\/b\u003e\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 Dawn of Refined Slim Automatics (1965):\u003c\/b\u003e In **1965**, the **Seikomatic-R** series was introduced as a sophisticated upgrade to the standard Seikomatic line. The reference **8305-0020** was produced by the **Suwa Seikosha** factory to meet the demands of high-ranking professionals who sought a more elegant, \"\"Refined\"\" timepiece. It arrived during a landmark year for Seiko, bridging the gap between practical business watches and elite luxury models like the King Seiko, symbolizing the quiet confidence of Japan's mid-60s economic leaders.\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eThe High-Grade 30-Jewel Caliber 8305 Heart:\u003c\/b\u003e This watch is powered by the **30-jewel Caliber 8305**, a premium automatic movement operating at **18,000 vibrations per hour (vph)**. In **1965**, a **30-jewel count** was an extraordinary mark of mechanical prestige. These synthetic rubies were strategically placed to minimize friction in the slender gear train and the high-efficiency winding system. This movement is celebrated for its remarkably thin profile, achieving a \"\"dress watch\"\" silhouette without sacrificing the convenience of automatic winding.\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eArchitectural \"\"0020\"\" Modernist Case:\u003c\/b\u003e The reference **8305-0020** features a sturdy yet slender stainless steel case with long, elegant lugs that follow the wrist's contour. A signature trait of this era is the **recessed crown at the 4 o'clock position**, which sits nearly flush with the case side. In **1965**, this design was a visual manifesto of Suwa Seikosha's engineering pride—communicating that the self-winding mechanism was so efficient that manual adjustment was rarely needed, resulting in a clean, aerodynamic profile.\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eMasterful \"\"Self-Data\"\" Dial Purity:\u003c\/b\u003e The dial of the **8305-0020** is a study in minimalist luxury, featuring a radiant sunburst silver finish and **hand-applied, multifaceted baton indices**. By focusing on the \"\"Self-Data\"\" (date only) complication at 3 o'clock, Seiko achieved a perfectly balanced and uncluttered layout. The applied **\"\"Seikomatic-R\"\" script** and the Suwa factory symbol remain prestigious hallmarks, emphasizing a professional aesthetic that prioritized clarity and timeless Swiss-rivaling elegance.\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eA Landmark of Suwa's \"\"Slender-Matic\"\" Legacy:\u003c\/b\u003e Produced in **1965**, the 8305-0020 remains a highly coveted reference for collectors of the \"\"Golden Era\"\" of Seiko automatics. It represents the perfect intersection of **mechanical complexity and the \"\"thin-is-luxury\"\" design philosophy** of the 1960s. It stands as a testament to an era when Suwa Seikosha perfected the **\"\"High-Jewel, Low-Profile\"\" automatic**, creating a reliable and dignified masterpiece that remains as stylish today as it was over half a century ago.\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\/w1223154936.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\u003cdiv style=\"text-align:center; background:#fff; padding:5px 0px 5px 0px; clear:both; width:100%;\"\u003e\n\u003cdiv style=\"padding-bottom:5px;\"\u003e\n\u003cspan\u003eeBay integration\u003c\/span\u003e by \u003c\/div\u003e\n\u003cimg width=\"120\" src=\"https:\/\/d31wxntiwn0x96.cloudfront.net\/ayjjhk\/\/images\/codisto-connect.png?width=200\u0026amp;nostretch\u0026amp;v=1\"\u003e\n\u003c\/div\u003e","brand":"NONKUN Japan","offers":[{"title":"Default Title","offer_id":52080602054977,"sku":"w1223154936","price":71200.0,"currency_code":"JPY","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0995\/8205\/0625\/files\/57_b684ddf9-d5fb-46ef-8bc0-4273e0df32b5.jpg?v=1786597850","url":"https:\/\/nonkun.com\/products\/serviced-vintage-1965-japan-seiko-seikomatic-r-8305-0020-30jewels-automatic-1","provider":"NONKUN Japan","version":"1.0","type":"link"}