{"title":"348 SR421SW Watch Batteries","description":"\u003cp\u003eThe 348 battery, also known by its IEC code SR421SW, is a 1.55V silver oxide button cell measuring about 4.8mm across and 2.1mm thick. Here you will find every 348 watch battery we stock, from Seiko and Seizaiken, so you can pick the brand you prefer.\u003c\/p\u003e\u003cp\u003eThe SW at the end of SR421SW means it is a low drain cell, made for watches with a low power draw such as most simple analogue quartz watches. If you are not sure which battery your watch takes, check the number printed on the old battery or search for it in our \u003ca href=\"\/pages\/watch-battery-guide\"\u003ewatch battery size chart\u003c\/a\u003e.\u003c\/p\u003e\u003cp\u003eUK delivery is free on every order, and orders placed before 2pm Monday to Friday are dispatched the same day.\u003c\/p\u003e","products":[{"product_id":"seizaiken-sr421sw-silver-oxide-watch-battery-genuine-japan-made-348-long-lasting-power","title":"Seizaiken 348 \/ SR421SW Silver Oxide Watch Battery","description":"\u003cp\u003e\u003cstrong\u003eSeizaiken 348 \/ SR421SW Silver Oxide Watch Battery\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eKeep your timepiece running accurately with the Seizaiken 348 \/ SR421SW silver oxide cell. Stable voltage and leak‑resistant design for dependable performance.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBattery size:\u003c\/strong\u003e 348 \/ SR421SW\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChemistry:\u003c\/strong\u003e Silver Oxide\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUse:\u003c\/strong\u003e Suitable for a wide range of analogue and digital watches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShelf life:\u003c\/strong\u003e Fresh stock, typically 3–5 years\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePackaging:\u003c\/strong\u003e Single retail pack (brand new, factory sealed)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cem\u003eTip:\u003c\/em\u003e Check your existing battery code or watch manual before ordering.\u003c\/p\u003e\n\u003cp\u003eFast UK dispatch from Chrono Straps UK.\u003c\/p\u003e","brand":"Seizaiken","offers":[{"title":"Default Title","offer_id":51360168378710,"sku":"SEIZAIKEN_348_SR421SW","price":3.51,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0939\/1439\/9062\/files\/Seizaiken_by_Seiko_348_SR421SW_Silver_Oxide_Watch_Battery.png?v=1762694487"},{"product_id":"seiko-348-sr421sw-1-55v-silver-oxide-mercury-free-watch-battery-made-in-japan","title":"Seiko 348 \/ SR421SW Silver Oxide Watch Battery","description":"\u003cp\u003e\u003cstrong\u003eSeiko 348 \/ SR421SW Silver Oxide Watch Battery\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eKeep your timepiece running accurately with the Seiko 348 \/ SR421SW silver oxide cell. Stable voltage and leak-resistant design for dependable performance.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBattery size:\u003c\/strong\u003e 348 \/ SR421SW\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChemistry:\u003c\/strong\u003e Silver Oxide\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUse:\u003c\/strong\u003e Suitable for a wide range of analogue and digital watches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShelf life:\u003c\/strong\u003e Fresh stock, typically 3-5 years\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePackaging:\u003c\/strong\u003e Single retail pack (brand new, factory sealed)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cem\u003eTip:\u003c\/em\u003e Check your existing battery code or watch manual before ordering.\u003c\/p\u003e\n\u003cp\u003eFast UK dispatch from Chrono Straps UK.\u003c\/p\u003e","brand":"Seiko","offers":[{"title":"Default Title","offer_id":51368318075222,"sku":"SEIKO_348_SR421SW","price":3.96,"currency_code":"GBP","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0939\/1439\/9062\/files\/Seiko_348_SR421SW_Silver_Oxide_Watch_Battery.png?v=1762697452"}],"url":"https:\/\/www.chronostraps.co.uk\/collections\/348-sr421sw-watch-battery.oembed","provider":"Chrono Straps UK","version":"1.0","type":"link"}