{"product_id":"438-viton-o-ring-90a-6-1-4-in-id-pack-of-25-high-temp-seal","title":"438 Viton O-Ring 90A, 6-1\/4 in ID (Pack of 25) - High Temp Seal","description":"\u003cp\u003eIn this review the Mr O-Ring 438 Viton O-Ring pack is evaluated for industrial sealing tasks where chemical and temperature resistance matter most. The bottom line: this pack of 25 delivers a consistent, high-hardness Viton seal for applications exposed to fuels, oils, ozone and elevated temperatures, so it is ideal for maintenance technicians, machine shops and fluid system installers who need reliable, repeatable replacements. The reviewer found the 90A durometer and actual dimensions provided good compression control and a long service life in demanding environments.\u003c\/p\u003e\u003ch2\u003eKey Features\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Viton FKM offers superior resistance to fuels, mineral oils and many organic solvents, reducing seal failures in hydrocarbon service.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDurometer:\u003c\/strong\u003e The 90A hardness gives a firm seal that resists extrusion and maintains shape under sustained pressure, useful for static and some dynamic sealing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTemperature range:\u003c\/strong\u003e Rated from -26C (-15F) to 232C (450F) so these o-rings tolerate high-temperature air and many hot fluids without rapid degradation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePack size:\u003c\/strong\u003e Supplied as a pack of 25 for repeat servicing and inventory, helping shops and field techs replace multiple seals without frequent reordering.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize accuracy:\u003c\/strong\u003e Nominal and measured dimensions (6-1\/4 in ID nominal; actual 6.225 in ID) provide predictable fit to AS568 sizing standards for easier selection.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eWho It's For\u003c\/h2\u003e\u003cp\u003eThe 438 Viton o-ring pack is best for industrial maintenance crews, HVAC and refrigeration technicians, and hydraulic or fuel-system repair shops that encounter petroleum products, diesel blends, silicone oils or high temperature environments. Its chemical compatibility and high temperature rating make it a good fit where longevity under stress is required.\u003c\/p\u003e\u003cp\u003eIt is less well suited for very soft-sealing applications that demand a low durometer material for delicate compression or for systems requiring FDA food-grade elastomers; in those cases a softer or food-safe elastomer should be considered.\u003c\/p\u003e\u003ch2\u003ePros \u0026amp; Cons\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003ePros\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eExcellent chemical resistance to fuels, oils, solvents and many acids, reducing replacement frequency.\u003c\/li\u003e\n\u003cli\u003eWide temperature tolerance that performs in both very hot and moderately cold conditions.\u003c\/li\u003e\n\u003cli\u003eConsistent 90A hardness gives reliable sealing and resistance to extrusion in pressurized applications.\u003c\/li\u003e\n\u003cli\u003ePack of 25 provides convenient stock for recurring maintenance tasks.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCons\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e90A durometer is relatively firm and may not seal as well in low-compression or irregular surfaces compared with softer compounds.\u003c\/li\u003e\n\u003cli\u003eNot intended where food-grade or very low temperature performance below -26C is required.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eSpecifications\u003c\/h2\u003e\u003ctable\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eMr O-Ring\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaterial\u003c\/td\u003e\n\u003ctd\u003eViton (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\u003e6-1\/4 in ID, 6-3\/4 in OD, 1\/4 in CS\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eActual dimensions\u003c\/td\u003e\n\u003ctd\u003e6.225 in ID, 6.775 in OD, 0.275 in 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\u003ePack size\u003c\/td\u003e\n\u003ctd\u003e25 pieces\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003ch2\u003eOur Verdict\u003c\/h2\u003e\u003cp\u003eThe Mr O-Ring 438 Viton o-ring pack is a practical choice for professionals needing durable, high-temperature seals compatible with fuels, oils and many chemicals. With precise AS568-sized dimensions and a firm 90A durometer, it offers good value for maintenance inventories and applications where longevity and chemical resistance matter most.\u003c\/p\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eAre these o-rings suitable for fuel systems?\u003c\/strong\u003e\u003cbr\u003eYes; Viton FKM resists petroleum, diesel and methanol or ethanol blends, making these appropriate for many fuel-system seals.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill the 90A hardness seal irregular surfaces?\u003c\/strong\u003e\u003cbr\u003eThe 90A durometer is firm and works best on properly machined or dimensional surfaces; softer compounds seal better on irregular or low-compression joints.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDo these meet a standard size?\u003c\/strong\u003e\u003cbr\u003eYes; the 438 size conforms to AS568 nominal sizing with the listed actual dimensions for reliable replacement selection.\u003c\/p\u003e","brand":"Mr O-Ring","offers":[{"title":"Default Title","offer_id":48633679839451,"sku":"B07R43K5FJ","price":270.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0724\/1043\/1707\/files\/51Kuv29LevL._SL1000_8b40e3ab-c771-4c2d-827b-b8bd16d7f3b2.jpg?v=1778497099","url":"https:\/\/gearmusthave.com\/products\/438-viton-o-ring-90a-6-1-4-in-id-pack-of-25-high-temp-seal","provider":"GearMustHave","version":"1.0","type":"link"}