{"product_id":"swartchild-black-shield-clock-mainspring-2-5-x-21-mm-x-17-ref-25-21-c-45","title":"Swartchild Black Shield Clock Mainspring 2.5 x .21 mm x 17¾\" Ref 25-21 B 45","description":"\u003cp\u003e\u003cstrong\u003eSwartchild \u0026amp; Co \u003cem\u003e\u003c\/em\u003e\u003c\/strong\u003e\u003cem\u003eBlack Shield\u003c\/em\u003e\u003cstrong\u003e\u003cem\u003e\u003c\/em\u003e\u003c\/strong\u003e Clock Mainspring, OPEN LOOP End, for Schuler 11, GR Ref. 25 - 21 B 45, steel, made in France. See images for precise mainspring specifications. I specialize is hard to find watch \u0026amp; clock parts and all parts are unconditionally guaranteed. Images do a pretty good job of representing the item\u003c\/p\u003e","brand":"Swartchild \u0026 Co","offers":[{"title":"Default Title","offer_id":48681442312500,"sku":"CMS-SW2521B45S-07","price":6.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0849\/3341\/1124\/files\/2025-07-1414.02.06.jpg?v=1752527045","url":"https:\/\/www.vintagetimeparts.com\/products\/swartchild-black-shield-clock-mainspring-2-5-x-21-mm-x-17-ref-25-21-c-45","provider":"Vintage Time Parts","version":"1.0","type":"link"}