{"product_id":"swisscraft-mainspring-2720-for-gruen-caliber-405-406-410-411-420-421-425-426-steel","title":"Swisscraft Mainspring #2720 for Gruen caliber 405, 406, 410, 411, 420, 421, 425, 426 - Steel","description":"\u003cp\u003e\u003cstrong\u003eSwisscraft \u003c\/strong\u003eMainspring #2720 for \u003cstrong\u003eGruen\u003c\/strong\u003e\u003cstrong\u003e \u003c\/strong\u003ecaliber 405, 406, 410, 411, 420, 421, 425, 426 movements, steel, new in envelope.  See images for precise mainspring specifications. I likely have several of these so the one you get may differ slightly from the images. I specialize in hard to find watch parts and all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item.\u003c\/p\u003e","brand":"Swisscraft","offers":[{"title":"Default Title","offer_id":48872997060916,"sku":"PMS-SWIS2720S-08","price":5.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0849\/3341\/1124\/files\/2025-08-2513.13.31.jpg?v=1756152961","url":"https:\/\/www.vintagetimeparts.com\/products\/swisscraft-mainspring-2720-for-gruen-caliber-405-406-410-411-420-421-425-426-steel","provider":"Vintage Time Parts","version":"1.0","type":"link"}