{"product_id":"mr-o-ring-347-viton-o-ring-90a-durometer-4-1-4in-id-durable-seal","title":"Mr O-Ring 347 Viton O-Ring 90A Durometer 4-1\/4in ID - Durable Seal","description":"\u003cp\u003eIn this review the Mr O-Ring 347 Viton O-Ring is evaluated for technicians and hobbyists who need a reliable, high-temperature seal in petroleum, fuel, or chemical environments. The bottom line: this pack of five 90A durometer Viton o-rings stands out for chemical and heat resistance, making it a practical choice when compatibility with fuels, oils, and solvents is the priority. The reviewer found the nominal and actual dimensions consistent, the hardness right for static and low-dynamic seals, and the listed temperature range useful for demanding applications.\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) provides excellent resistance to petroleum, fuels, many chemicals and solvents, which reduces seal failures in aggressive fluids.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDurometer:\u003c\/strong\u003e 90A hardness offers a firm seal useful for static and some dynamic sealing tasks while maintaining resilience under load.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDimensions:\u003c\/strong\u003e Nominal 4-1\/4in ID and 4-5\/8in OD with actual dimensions close to nominal, improving fit reliability in standard AS568 applications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTemperature range:\u003c\/strong\u003e Rated from -26C (-15F) to 232C (450F), suitable for very high temperature air and many industrial service conditions.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePack quantity:\u003c\/strong\u003e Sold as a pack of five, which is convenient for small maintenance jobs or replacement spares without overstocking.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandards:\u003c\/strong\u003e Sized to AS568 conventions, simplifying selection for established equipment and replacement parts lists.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eWho It's For\u003c\/h2\u003e\n\u003cp\u003eThe Mr O-Ring 347 Viton is aimed at professionals and experienced DIYers working with fuels, mineral oils, hydraulic fluids, silicone oils, or in environments exposed to ozone and weather. It is a good choice where elevated temperature resistance and chemical compatibility matter, such as engine components, fuel systems, or industrial machinery.\u003c\/p\u003e\n\u003cp\u003eThose who need very soft, low-durometer seals for delicate dynamic shafts or consumers seeking a generic household replacement without specific chemical exposure should consider different materials or hardness. This product is optimized for chemical resistance and heat rather than ultra-low friction dynamic sealing.\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 and high-temperature resistance from the Viton\/FKM compound.\u003c\/li\u003e\n\u003cli\u003eFirm 90A durometer provides durable sealing for static applications and many service conditions.\u003c\/li\u003e\n\u003cli\u003eActual dimensions are listed alongside nominal sizes, helping to confirm fit before installation.\u003c\/li\u003e\n\u003cli\u003ePack of five offers ready spares for maintenance without bulk purchasing.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eCons\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e90A hardness may be too stiff for some dynamic shaft seals where lower friction is required.\u003c\/li\u003e\n\u003cli\u003eNot the best choice for extreme low-temperature flexibility below the stated range.\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 ID\u003c\/td\u003e\n\u003ctd\u003e4-1\/4in\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNominal OD\u003c\/td\u003e\n\u003ctd\u003e4-5\/8in\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNominal cross-section\u003c\/td\u003e\n\u003ctd\u003e3\/16in\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eActual dimensions\u003c\/td\u003e\n\u003ctd\u003e4.225in ID, 4.645in OD, 0.210in 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\u003c\/table\u003e\n\u003ch2\u003eOur Verdict\u003c\/h2\u003e\n\u003cp\u003eThe Mr O-Ring 347 Viton 90A is a solid value for anyone needing chemical and heat-resistant seals in petroleum and fuel-exposed systems. Its firm durometer and AS568 sizing make it a practical replacement part for maintenance and repairs, though installers should choose a lower-durometer material when maximum flexibility or low-friction dynamic sealing is required.\u003c\/p\u003e\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eAre these o-rings compatible with gasoline and diesel?\u003c\/strong\u003e\u003cbr\u003eYes, the Viton compound is formulated to perform well in gasoline, diesel and many fuel blends noted in the product description.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDo the actual dimensions differ from the nominal sizes?\u003c\/strong\u003e\u003cbr\u003eThe listing provides actual dimensions (4.225in ID, 4.645in OD, 0.210in CS) which are close to the nominal sizes for reliable fit verification.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan these be used at high temperatures?\u003c\/strong\u003e\u003cbr\u003eYes, they are rated up to 232C (450F), suitable for many high temperature air and industrial applications.\u003c\/p\u003e","brand":"Mr O-Ring","offers":[{"title":"Default Title","offer_id":48248909037787,"sku":"B07R62RZLK","price":36.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0724\/1043\/1707\/files\/51Kuv29LevL._SL1000_3e4d2f46-452d-46da-8ee8-c2321ddc7a74.jpg?v=1776271499","url":"https:\/\/gearmusthave.com\/products\/mr-o-ring-347-viton-o-ring-90a-durometer-4-1-4in-id-durable-seal","provider":"GearMustHave","version":"1.0","type":"link"}