{"product_id":"seiko-s-284-kojiake-gehauseoffner-fur-sprungboden-schmale-klinge-4-mm-original-seiko-japan","title":"SEIKO S-284 Kojiake – Case Opener for Snap-On Backs, Narrow Blade 4 mm | Original SEIKO Japan","description":"\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003eOriginal SEIKO watchmaker's tool, imported directly from Japan – rarely available outside of Japan.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003eThe Kojiake (こじ開け, \"lever opener\") is the classic Japanese tool for opening snap-on and press-on casebacks. The S-284 version from the professional SEIKO tool range features a particularly narrow blade with a tip width of only 4 mm, making it designed for cases with extremely narrow opening notches – such as small ladies' watches and vintage cases where wider case knives cannot even engage the narrow caseback notch.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003eA special feature of the SEIKO Kojiake: The blade is deliberately designed so that it can be resharpened by the watchmaker and adapted to the respective case – as is common in Japanese workshops. The tool thus grows with its tasks and, with good care, lasts a watchmaker's lifetime.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003eThe series includes three blade widths: S-282 (8 mm), S-283 (5 mm) and S-284 (4 mm, this listing).\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003e\u003cstrong\u003eWhat differentiates the tool from European counterparts:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003eEuropean case knives are predominantly designed as wide universal blades. For the narrow opening notches, which are common especially in Japanese watches – including many vintage models from SEIKO and Citizen – the appropriate narrow version is usually missing in European trade: A blade that is too wide cannot get a grip in the notch and slips off, with a corresponding risk of scratches. The S-284 is the tool with which these casebacks are opened ex-factory – from the original SEIKO tool range, which is not regularly distributed in Europe. In addition, there is the resharpenable blade: Cheap openers with soft blades bend at the tip and have to be replaced; the SEIKO Kojiake is resharpened instead.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003e\u003cstrong\u003eDimensions:\u003c\/strong\u003e\u003cbr\u003eTip width 4 mm\u003cbr\u003eReference: SEIKO S-284 (SE-S-284)\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003e\u003cstrong\u003eCondition:\u003c\/strong\u003e\u003cbr\u003eNew, original packaging\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003eNote\u003cbr\u003eImproper use of tools can damage watches. Use is at your own risk.\u003c\/p\u003e","brand":"Vintage \u0026 JDM (Japan Domestic Market)","offers":[{"title":"Default Title","offer_id":53924431266130,"sku":null,"price":24.9,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0911\/3908\/0530\/files\/rn-image_picker_lib_temp_d53c082e-7478-493f-9799-097802c45b3a.jpg?v=1783396948","url":"https:\/\/japanese-microbrands.com\/en\/products\/seiko-s-284-kojiake-gehauseoffner-fur-sprungboden-schmale-klinge-4-mm-original-seiko-japan","provider":"Japanese Microbrands - Mario Lenke","version":"1.0","type":"link"}