{"title":"Inner Diameter - 21.5mm","description":"\u003ch1\u003e21.5mm\u003c\/h1\u003e\u003ch2\u003e21.5mm Online shopping\u003c\/h2\u003e","products":[{"product_id":"mr3121-2rs-full-complement-ceramic","title":"MR3121-2RS Full Complement Full Ceramic Bearing 21.5x31x7 ZrO2 Bearing","description":"\u003ccenter\u003e\n\u003ctable cellspacing=\"2\" cellpadding=\"10\" bg=\"\" border=\"1\"\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"center\"\u003e\u003cfont face=\"Tahoma\" size=\"+2\"\u003eMR3121-2RS Full Complement            Ceramic Sealed Ball Bearing\u003cbr\u003e            Zirconia\u003cbr\u003e            21.5mm x 31mm x 7mm\u003c\/font\u003e\u003c\/td\u003e\u003c\/tr\u003e\u003c\/tbody\u003e\u003c\/table\u003e\n\u003cbr\u003e\u003cbr\u003e\u003ctable cellspacing=\"2\" cellpadding=\"5\" bg=\"\" border=\"0\"\u003e\u003ctbody\u003e\u003ctr\u003e\n\u003ctd\u003e\u003ctable cellspacing=\"3\" cellpadding=\"5\" bg=\"\" border=\"0\"\u003e\u003ctbody\u003e\n\u003ctr\u003e\u003ctd valign=\"center\" align=\"middle\"\u003e\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd valign=\"center\" align=\"middle\"\u003e\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\u003c\/td\u003e\n\u003ctd valign=\"top\" align=\"left\"\u003e\n\u003cp align=\"justify\"\u003e\u003cfont face=\"tahoma\"\u003eMR3121-2RS Full Complement Ceramic              sealed Ball Bearing, measures an inner diameter of 21.5mm,              outer diameter is 31mm and the width is 7mm, Bearing is made from ZrO2 Ceramic Zirconium oxide.\u003c\/font\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eMR3121-2RS Ball                Bearing\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eFull Complement Ceramic                Ball Bearing\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eCage: No Cage\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eBalls: ZRO2 Ceramic\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eClosures: PTFE covers\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eInner\/outer races:ZRO2                Ceramic\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eDimensions: 21.5 mm x 31mm x                7mm\/Metric\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eID (inner diameter)\/Bore:                21.5mm\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eOD (outer diameter): 31mm\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eWidth:                7mm\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eSize:21.5 x 31 x 7 mm\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eQuantity:One Bearing\u003c\/font\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\u003c\/tbody\u003e\u003c\/table\u003e\n\u003c\/center\u003e\u003cp\u003e\u003cbr\u003e\u003c\/p\u003e\u003ccenter\u003e\u003c\/center\u003e","brand":"VXB","offers":[{"title":"Default Title","offer_id":49309911711937,"sku":"Kit8448","price":49.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0828\/0955\/3089\/files\/mr3121-2rs-full-complement-ceramic-bearing-21-5x31x7-zro2-bearings-vxb-ball-bearings_2b8b1d92-14de-473b-8956-3e8b2c270c95.jpg?v=1748646701"},{"product_id":"smr3121-5-2rs-ceramic-bearing-21-5","title":"SMR3121.5-2RS Ceramic Bearing 21.5x31x7 Si3N4 PTFE ABEC-5 Bearing","description":"\u003ccenter\u003e\n\u003ctable cellspacing=\"2\" cellpadding=\"10\" bg=\"\" border=\"1\"\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"center\"\u003e\u003cfont face=\"Tahoma\" size=\"+2\"\u003e21.5 x 31 x 7 Stainless            Steel Premium ABEC-5 Ball Bearing\u003cbr\u003e            Silicon Nitride Ceramic Balls\u003cbr\u003e            2 PTFE Seals\u003c\/font\u003e\u003c\/td\u003e\u003c\/tr\u003e\u003c\/tbody\u003e\u003c\/table\u003e\n\u003cbr\u003e\u003cbr\u003e\u003ctable cellspacing=\"2\" cellpadding=\"10\" bg=\"\" border=\"0\"\u003e\u003ctbody\u003e\u003ctr\u003e\n\u003ctd valign=\"center\" align=\"center\" width=\"15%\"\u003e\u003ctable cellspacing=\"3\" cellpadding=\"5\" bg=\"\" border=\"0\"\u003e\u003ctbody\u003e\n\u003ctr\u003e\u003ctd valign=\"center\" align=\"center\"\u003e\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd valign=\"center\" align=\"center\"\u003e\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\u003c\/td\u003e\n\u003ctd align=\"left\" valign=\"top\" width=\"75%\"\u003e\n\u003cp align=\"justify\"\u003e\u003cfont face=\"tahoma\"\u003e21.5 x 31 x 7 Stainless Steel              Premium ABEC-5 Ball Bearing, Silicon Nitride ceramic              balls, inner diameter is 21.5mm, outer diameter is 31mm              and width is 7mm.\u003c\/font\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003e21.5 x 31 x 7 Ball                Bearing\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eDeep Groove Radial Ball                Bearing\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eClosures: PTFE Sealed\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eQuality: Premium ABEC-5\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eMaterial: Stainless Steel\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eBalls: Silicon Nitride Ceramic                (Si3N4)\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eLubrication: Self Lubricated                (Grease SRL) Bearing\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eDimensions: 21.5mm x 31mm x                7mm\/Metric\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eID (inner diameter)\/Bore:                21.5mm\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eOD (outer diameter): 31mm\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eWidth:                7mm\u003c\/font\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cfont face=\"tahoma\"\u003eQuantity: 1 Bearing\u003c\/font\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\u003c\/tbody\u003e\u003c\/table\u003e\n\u003c\/center\u003e\u003c!--Beginning HYBRID CERAMIC BEARINGS--\u003e\u003cp\u003e\u003cbr\u003e\u003csmall\u003e\u003cem\u003eVXB Category: Hybrid ceramic    bearings\u003c\/em\u003e\u003c\/small\u003e\u003cbr\u003e\u003c!--Ending HYBRID CERAMIC BEARINGS--\u003e\u003cbr\u003e\u003c\/p\u003e\u003cp\u003e\u003cbr\u003e\u003c\/p\u003e\u003cbr\u003e\u003ch3\u003e💡 What Does ABEC-5 Mean?\u003c\/h3\u003e \u003cp\u003e\u003cstrong\u003eABEC-5\u003c\/strong\u003e is a precision rating from the \u003cem\u003eAnnular Bearing Engineers’ Committee (ABEC)\u003c\/em\u003e, indicating that the bearing is manufactured with \u003cstrong\u003etighter tolerances\u003c\/strong\u003e for improved accuracy and performance.\u003c\/p\u003e \u003cp\u003eBearings rated ABEC-5 are designed for \u003cstrong\u003ehigh-speed, low-friction operation\u003c\/strong\u003e, making them ideal for electric motors, precision tools, 3D printers, and performance equipment where smooth rotation and long service life are essential.\u003c\/p\u003e","brand":"VXB","offers":[{"title":"Default Title","offer_id":49310025646273,"sku":"Kit11865","price":29.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0828\/0955\/3089\/files\/smr3121-5-2rs-ceramic-bearing-21-5x31x7-si3n4-ptfe-abec-5-bearings-vxb-ball-bearings_13946f1d-127a-4dd8-b27b-246f77d40746.jpg?v=1748646745"},{"product_id":"smr3121-5-ceramic-bearing-21-5mm-m","title":"SMR3121.5 Ceramic Bearing 21.5mm Metric Sealed ABEC-5 Bearing","description":"\u003ccenter\u003e\n\u003ctable cellspacing=\"2\" cellpadding=\"10\" bg=\"\" border=\"1\"\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"Center\"\u003e\u003cfont face=\"Tahoma\" size=\"+2\"\u003eSMR3121.5 Premium ABEC-5 Stainless Steel Ball Bearing\u003cbr\u003eSilicon Nitride Ceramic Balls\u003cbr\u003e 21.5 x 31 x 7 mm\u003c\/font\u003e\u003c\/td\u003e\u003c\/tr\u003e\u003c\/tbody\u003e\u003c\/table\u003e\n\u003cbr\u003e\u003cbr\u003e\u003ctable cellspacing=\"2\" cellpadding=\"5\" bg=\"\" border=\"1\"\u003e\u003ctbody\u003e\u003ctr\u003e\n\u003ctd valign=\"center\" align=\"Center\" width=\"\"\u003e\u003ctable cellspacing=\"3\" cellpadding=\"5\" bg=\"\" border=\"0\"\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd valign=\"center\" align=\"Center\"\u003e\u003c\/td\u003e\u003c\/tr\u003e\u003c\/tbody\u003e\u003c\/table\u003e\u003c\/td\u003e\n\u003ctd align=\"left\" valign=\"top\" width=\"\"\u003e\u003cfont face=\"tahoma\"\u003e\u003cp align=\"justify\"\u003eSMR3121.5 Premium ABEC-5 Stainless Steel Ball Bearing, bearing is Silicon Nitride ceramic ball.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eSMR3121.5 Ball Bearing\u003c\/li\u003e\n\u003cli\u003eQuality: Premium ABEC-5\u003c\/li\u003e\n\u003cli\u003eClosures: Open\u003c\/li\u003e\n\u003cli\u003eMaterial: Stainless Steel \u003c\/li\u003e\n\u003cli\u003eBalls: Silicon Nitride Ceramic (Si3N4) \u003c\/li\u003e\n\u003cli\u003eDimensions: 21.5mm x 31mm x 7mm\/Metric\u003c\/li\u003e\n\u003cli\u003eID (inner diameter)\/Bore: 21.5mm\u003c\/li\u003e\n\u003cli\u003eOD (outer diameter): 31mm\u003c\/li\u003e\n\u003cli\u003eWidth: 7mm\u003c\/li\u003e\n\u003cli\u003eDimensions: 21.5 x 31 x 7 mm\u003c\/li\u003e\n\u003cli\u003eQuantity: 1 Bearing \u003c\/li\u003e\n\u003c\/ul\u003e\u003c\/font\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\u003c\/tbody\u003e\u003c\/table\u003e\n\u003c\/center\u003e\u003c!--Beginning HYBRID CERAMIC BEARINGS--\u003e\u003cbr\u003e\u003csmall\u003e\u003ci\u003eVXB Category: Hybrid ceramic bearings\u003c\/i\u003e\u003c\/small\u003e\u003cbr\u003e\u003c!--Ending HYBRID CERAMIC BEARINGS--\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003ch3\u003e💡 What Does ABEC-5 Mean?\u003c\/h3\u003e \u003cp\u003e\u003cstrong\u003eABEC-5\u003c\/strong\u003e is a precision rating from the \u003cem\u003eAnnular Bearing Engineers’ Committee (ABEC)\u003c\/em\u003e, indicating that the bearing is manufactured with \u003cstrong\u003etighter tolerances\u003c\/strong\u003e for improved accuracy and performance.\u003c\/p\u003e \u003cp\u003eBearings rated ABEC-5 are designed for \u003cstrong\u003ehigh-speed, low-friction operation\u003c\/strong\u003e, making them ideal for electric motors, precision tools, 3D printers, and performance equipment where smooth rotation and long service life are essential.\u003c\/p\u003e","brand":"VXB","offers":[{"title":"Default Title","offer_id":49310089248961,"sku":"Kit13043","price":29.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0828\/0955\/3089\/files\/smr3121-5-ceramic-bearing-21-5mm-metric-sealed-abec-5-bearings-vxb-ball-bearings-1_2f91f7a1-ec6f-4462-ba4e-246807cd03a0.jpg?v=1748646751"},{"product_id":"215317-2rs-sealed-bearing-21-5x31x","title":"Rodamiento sellado 215317-2RS 21.5x31x7 métrico","description":"\u003ccenter\u003e\n\u003ctable cellspacing=\"2\" cellpadding=\"10\" bg border=\"1\"\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"center\"\u003e\u003cfont face=\"Tahoma\" size=\"+2\"\u003eRodamiento de bolas sellado 215317-2RS\u003cbr\u003e21.5mm x 31mm x 7mm\u003c\/font\u003e\u003c\/td\u003e\u003c\/tr\u003e\u003c\/tbody\u003e\u003c\/table\u003e\n\u003cbr\u003e\u003cbr\u003e\u003ctable cellspacing=\"2\" cellpadding=\"5\" width=\"85%\" bg border=\"0\"\u003e\u003ctbody\u003e\u003ctr\u003e\n\u003ctd align=\"center\" valign=\"center\"\u003e\u003ctable cellspacing=\"3\" cellpadding=\"5\" bg border=\"0\"\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd valign=\"center\" align=\"Center\"\u003e\u003c\/td\u003e\u003c\/tr\u003e\u003c\/tbody\u003e\u003c\/table\u003e\u003c\/td\u003e\n\u003ctd valign=\"top\" align=\"left\"\u003e\u003cfont face=\"Tahoma\"\u003e\u003cp align=\"justify\"\u003eRodamiento de bolas sellado 215317-2RS, fabricado en acero cromado con bolas de acero cromado y jaula de acero, el rodamiento 215317-2RS está cerrado con sellos de goma para protegerlo del polvo o cualquier posible contaminación, el rodamiento está sellado y auto-lubricado, la calidad está establecida en EMQ (calidad para motores eléctricos) para garantizar alta velocidad, el rodamiento 215317-2RS está lubricado con grasa.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eRodamiento de bolas 215317-2RS\u003c\/li\u003e\n\u003cli\u003eRodamiento de bolas radial de ranura profunda\u003c\/li\u003e\n\u003cli\u003eJaula: Acero\u003c\/li\u003e\n\u003cli\u003eMaterial: Acero cromado\u003c\/li\u003e\n\u003cli\u003eBolas: Acero cromado\u003c\/li\u003e\n\u003cli\u003eJuego radial: C0\u003c\/li\u003e\n\u003cli\u003eCalidad: Calidad para motores eléctricos\u003c\/li\u003e\n\u003cli\u003eLubricación: Pre-lubricado con grasa\u003c\/li\u003e\n\u003cli\u003eCierres: Doble sellado con sellos de goma RS\/RS1\/2RS1\u003c\/li\u003e\n\u003cli\u003eTamaño: 21.5mm x 31mm x 7mm\u003c\/li\u003e\n\u003cli\u003eDiámetro interior del rodamiento: 21.5mm\u003c\/li\u003e\n\u003cli\u003eDiámetro exterior del rodamiento: 31mm\u003c\/li\u003e\n\u003cli\u003eAncho del rodamiento: 7mm\u003c\/li\u003e\n\u003cli\u003eCantidad: 1 Rodamiento\u003c\/li\u003e\n\u003c\/ul\u003e\u003c\/font\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\u003c\/tbody\u003e\u003c\/table\u003e\n\u003c\/center\u003e\u003cbr\u003e","brand":"VXB","offers":[{"title":"Default Title","offer_id":49310389567681,"sku":"Kit21084","price":34.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0828\/0955\/3089\/files\/215317-2rs-sealed-bearing-21-5x31x7-metric-vxb-ball-bearings-1_abeeb402-35a3-4592-9c8d-c42b3912326f.jpg?v=1748646821"},{"product_id":"mr3121-5-full-ceramic-bearing-21-5","title":"MR3121.5 Full Ceramic Bearing 21.5x31x7mm ID Bore 21.5mm","description":"\u003ccenter\u003e\n\u003ctable cellspacing=\"2\" cellpadding=\"10\" bg=\"\" border=\"1\"\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"Center\"\u003e\u003cfont face=\"Tahoma\" size=\"+2\"\u003e6804 Modified Ball Bearing\u003cbr\u003eFull Ceramic\u003cbr\u003e21.5mm x 31mm x 7mm\u003c\/font\u003e\u003c\/td\u003e\u003c\/tr\u003e\u003c\/tbody\u003e\u003c\/table\u003e\n\u003cbr\u003e\u003cbr\u003e\u003ctable cellspacing=\"2\" cellpadding=\"5\" width=\"80%\" bg=\"\" border=\"0\"\u003e\u003ctbody\u003e\u003ctr\u003e\n\u003ctd align=\"center\" valign=\"center\"\u003e\u003ctable cellspacing=\"3\" cellpadding=\"5\" bg=\"\" border=\"0\"\u003e\u003ctbody\u003e\n\u003ctr\u003e\u003ctd valign=\"center\" align=\"middle\"\u003e\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd valign=\"center\" align=\"middle\"\u003e\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\u003c\/td\u003e\n\u003ctd valign=\"top\" align=\"left\"\u003e\u003cfont face=\"tahoma\"\u003e\u003cp align=\"justify\"\u003e  \t\t\tFull Ceramic Ball Bearing, measures an inner diameter of 21.5mm, outer diameter is 31mm and the width is 7mm, a standard bearing size commonly used in a variety of industrial and commercial applications, Bearing is made from Ceramic.  \t\t\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e6804 Modified Ball bearing\u003c\/li\u003e\n\u003cli\u003eFull Ceramic Ball Bearing\u003c\/li\u003e\n\u003cli\u003eBalls: Made from Zirconia Ceramic (ZrO₂)\u003c\/li\u003e\n\u003cli\u003eCage Material: PTFE (Polytetrafluoroethylene)\u003c\/li\u003e\n\u003cli\u003eRaces Material: Zirconia (ZrO₂) Ceramic \u003c\/li\u003e\n\u003cli\u003eDimensions: 21.5mm x 31mm x 7mm\/Metric\u003c\/li\u003e\n\u003cli\u003eID (inner diameter)\/Bore: 21.5mm\u003c\/li\u003e\n\u003cli\u003eOD (outer diameter): 31mm\u003c\/li\u003e\n\u003cli\u003eWidth: 7mm\u003c\/li\u003e\n\u003cli\u003eSize: 21.5 x 31 x 7 mm\u003c\/li\u003e\n\u003cli\u003eQuantity: One ball bearing\u003c\/li\u003e\n\u003c\/ul\u003e\u003c\/font\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\u003c\/tbody\u003e\u003c\/table\u003e\n\u003c\/center\u003e\u003c!--Beginning FULL CERAMIC BEARINGS--\u003e\u003cbr\u003e\u003csmall\u003e\u003ci\u003eVXB Category: Full ceramic bearings\u003c\/i\u003e\u003c\/small\u003e\u003cbr\u003e\u003c!--Ending FULL CERAMIC BEARINGS--\u003e\u003cbr\u003e\u003cbr\u003e","brand":"VXB","offers":[{"title":"Default Title","offer_id":49310708236481,"sku":"Kit7757","price":49.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0828\/0955\/3089\/files\/mr3121-5-full-ceramic-bearing-21-5x31x7-vxb-ball-bearings_040b2a52-3728-4773-bb5c-5d2f636147c8.jpg?v=1748646872"}],"url":"https:\/\/smallbearings.com\/es\/collections\/inner-diameter-21-5mm.oembed","provider":"Small Bearings","version":"1.0","type":"link"}