{"product_id":"mr-o-ring-359-viton-o-ring-90a-durometer-5-3-4-in-id-pack-of-10","title":"Mr O-Ring 359 Viton O-Ring 90A Durometer, 5-3\/4 in ID Pack of 10","description":"\u003cp\u003eIn this review the Mr O-Ring 359 Viton O-Ring is assessed for mechanics, hobbyists, and industrial users who need a durable sealing solution that resists fuels and high temperatures. The bottom line: this pack of ten 90A durometer Viton o-rings is best for applications where chemical resistance and thermal stability matter most, offering the right balance of firmness and elasticity for repeated sealing under harsh conditions.\u003c\/p\u003e\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Fluorocarbon rubber (Viton\/FKM) delivers strong resistance to fuels, oils, solvents and many chemicals so seals last longer in aggressive environments.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTemperature range:\u003c\/strong\u003e Rated from -26C to 232C (-15F to 450F), providing dependable performance across very low to very high operating temperatures.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDurometer hardness:\u003c\/strong\u003e At 90A durometer the o-ring holds its shape under compression, reducing extrusion and improving long-term sealing in static and some dynamic uses.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDimensions:\u003c\/strong\u003e Nominal 5-3\/4 in ID, 6-1\/8 in OD and 3\/16 in cross-section with actual dimensions close to 5.725 in ID and 6.145 in OD for reliable fit in standard AS568 sized grooves.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePack quantity:\u003c\/strong\u003e Sold as a pack of 10 which is convenient for repeat maintenance tasks or stocking common replacement sizes.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplication range:\u003c\/strong\u003e Performs well with petroleum fuels, biodiesel blends, silicone oils, high vacuum and ozone exposure, extending usable service life in varied systems.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eWho It's For\u003c\/h2\u003e\n\u003cp\u003eThis product is aimed at technicians, machine shops, marine and automotive repair shops, and enthusiasts who require a robust seal that tolerates fuels, high temperatures and aggressive chemicals. The 90A hardness and Viton compound make it suitable for static seals or slow-moving shafts where chemical compatibility is critical.\u003c\/p\u003e\n\u003cp\u003eThose needing softer, more flexible o-rings for low-pressure dynamic seals or food-grade silicone alternatives should look elsewhere, as the 90A Viton compound prioritizes chemical and heat resistance over extreme elasticity.\u003c\/p\u003e\n\u003ch2\u003ePros \u0026amp; Cons\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003ePros\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eExcellent chemical resistance to fuels, oils and many solvents, so seals endure harsh service conditions.\u003c\/li\u003e\n\u003cli\u003eHigh temperature capability to 232C (450F) allows use in engines and heated systems without rapid degradation.\u003c\/li\u003e\n\u003cli\u003eConsistent 90A hardness provides firm sealing and reduces extrusion in many groove designs.\u003c\/li\u003e\n\u003cli\u003ePack of 10 offers good value for maintenance and replacement needs.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eCons\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eHigher durometer means less flexibility for very low-pressure dynamic sealing where softer compounds perform better.\u003c\/li\u003e\n\u003cli\u003eViton is not suitable for certain specialized chemistries not listed in the product description, so verify compatibility for exotic media.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003ctable\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaterial\u003c\/td\u003e\n\u003ctd\u003eViton (Fluorocarbon rubber, FKM)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDurometer\u003c\/td\u003e\n\u003ctd\u003e90A\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNominal dimensions\u003c\/td\u003e\n\u003ctd\u003e5-3\/4 in ID, 6-1\/8 in OD, 3\/16 in CS\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eActual dimensions\u003c\/td\u003e\n\u003ctd\u003e5.725 in ID, 6.145 in OD, 0.210 in CS\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMetric dimensions\u003c\/td\u003e\n\u003ctd\u003e145.42 mm ID, 156.08 mm OD, 5.33 mm CS\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTemperature range\u003c\/td\u003e\n\u003ctd\u003e-26C (-15F) to 232C (450F)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eQuantity\u003c\/td\u003e\n\u003ctd\u003ePack of 10\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003ch2\u003eOur Verdict\u003c\/h2\u003e\n\u003cp\u003eThe Mr O-Ring 359 Viton 90A o-ring is a practical choice for anyone needing a heat- and chemical-resistant seal in automotive, industrial or marine systems; the pack of ten and AS568-compliant sizing make it good value for maintenance shops and serious hobbyists who prioritize longevity and compatibility over extreme softness.\u003c\/p\u003e\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eAre these o-rings suitable for fuel exposure?\u003c\/strong\u003e\u003cbr\u003eYes, the Viton compound is specified to perform well with petroleum products, fuel blends and biodiesel mixes.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDo they meet standard sizing?\u003c\/strong\u003e\u003cbr\u003eThey meet AS568 size definitions with nominal and actual dimensions provided for reliable fit.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan they be used for high temperature applications?\u003c\/strong\u003e\u003cbr\u003eYes, they are rated to 232C (450F) for high temperature sealing tasks.\u003c\/p\u003e","brand":"Mr O-Ring","offers":[{"title":"Default Title","offer_id":48205193707739,"sku":"B07R74T29N","price":93.49,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0724\/1043\/1707\/files\/51Kuv29LevL._SL1000_ad75cb61-1bae-4e71-a6d1-9cb10eae162c.jpg?v=1770239095","url":"https:\/\/gearmusthave.com\/products\/mr-o-ring-359-viton-o-ring-90a-durometer-5-3-4-in-id-pack-of-10","provider":"GearMustHave","version":"1.0","type":"link"}