{"product_id":"usr-mainspring-for-hamilton-6-0s-no-1721-steel","title":"USR Mainspring for Hamilton 6\/0s No. 1721 - Steel","description":"\u003cp\u003e\u003cstrong\u003eUSR \u003c\/strong\u003esteel mainspring for \u003cstrong\u003eHamilton\u003c\/strong\u003e\u003cstrong\u003e \u003c\/strong\u003e6\/0s movements, Factory No. 1721, new in envelope. See images for precise mainspring specifications. I specialize is 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\/p\u003e","brand":"USR","offers":[{"title":"Default Title","offer_id":48878239088948,"sku":"PMA-USR1721S-09","price":4.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0849\/3341\/1124\/files\/2025-08-2909.39.14.jpg?v=1756485823","url":"https:\/\/www.vintagetimeparts.com\/products\/usr-mainspring-for-hamilton-6-0s-no-1721-steel","provider":"Vintage Time Parts","version":"1.0","type":"link"}