{"product_id":"swartchild-black-shield-super-mainspring-for-as-1299-tavannes-404-langendorf-816-alloy","title":"Swartchild Black Shield SUPER Mainspring for AS 1299, Tavannes 404, Langendorf 816 - Alloy","description":"\u003cp\u003e\u003cspan style=\"font-size: 14px;\"\u003e\u003cstrong\u003eSwartchild \u003c\/strong\u003e\u003cem\u003eBlack Shield \u003c\/em\u003eSUPER Mainspring for AS 1299, Tavannes 404 \u0026amp; Langendorf 816 caliber movements plus similar ébauche watches, white alloy, 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 so I usually have whatever you might need and all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item. \u003c\/span\u003e\u003c\/p\u003e","brand":"Swartchild","offers":[{"title":"Default Title","offer_id":48795579679028,"sku":"PMS-SBSM1299A-08","price":10.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0849\/3341\/1124\/files\/2025-08-0415.49.52.jpg?v=1754348010","url":"https:\/\/www.vintagetimeparts.com\/products\/swartchild-black-shield-super-mainspring-for-as-1299-tavannes-404-langendorf-816-alloy","provider":"Vintage Time Parts","version":"1.0","type":"link"}