{"product_id":"watch-craft-mainspring-3155m-for-utc-229-seiko-69-66a-mastertime-m112-m113-alloy","title":"Marco Marshalloy Mainspring 3155M for UTC 229, Seiko 69, 66A, Phenix 350, 355, 400 - Alloy","description":"\u003cp\u003e\u003cstrong\u003eMarco \u003c\/strong\u003e\u003cem\u003eMarshalloy\u003c\/em\u003e\u003cstrong\u003e \u003c\/strong\u003eMainspring 3155M for Unitime (UTC) 229, Seiko Sportsman, 69, 66A, A201, A202, Phenix 350, 355, 400 caliber movements, plus similar ébauche watches including numerous UTC 229 based watches (Mastertime 112, 113, Helbros, etc.), white alloy, new in envelope. See images for precise mainspring specifications. 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\/p\u003e","brand":"C \u0026 E Marshall","offers":[{"title":"Default Title","offer_id":49368094736692,"sku":"PMS-CEM3155MA-11","price":12.5,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0849\/3341\/1124\/files\/2026-11-0511.09.22.jpg?v=1793906241","url":"https:\/\/www.vintagetimeparts.com\/products\/watch-craft-mainspring-3155m-for-utc-229-seiko-69-66a-mastertime-m112-m113-alloy","provider":"Vintage Time Parts","version":"1.0","type":"link"}