{"product_id":"mr-o-ring-157-viton-o-ring-4-1-2-in-id-pack-of-25","title":"Mr O-Ring 157 Viton O-Ring 4-1\/2 in ID - Pack of 25","description":"\u003cp\u003eIn this review the reviewer focuses on the Mr O-Ring 157 Viton O-Ring pack of 25 and who will get the most value from it. The bottom line: this set is for technicians, hobbyists and maintenance teams who need reliable, high-temperature sealing in petroleum and chemical environments; the single biggest reason to buy is the material performance - a 90A durometer Viton (FKM) compound that resists fuels, oils, ozone and high heat. The reviewer found the nominal and actual sizes close enough for AS568 applications and appreciated the metric equivalents provided for planning and inventory.\u003c\/p\u003e\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Viton (FKM) delivers strong resistance to fuels, mineral oils and many organic solvents for longer service life in harsh fluids.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHardness:\u003c\/strong\u003e The 90A durometer balances elasticity and compression set resistance so seals maintain contact under pressure and temperature changes.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTemperature range:\u003c\/strong\u003e Rated from -26C to 232C (-15F to 450F), useful for hot engine bays, ovens and high temperature process lines.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize accuracy:\u003c\/strong\u003e Actual dimensions (4.487 in ID, 4.693 in OD, 0.103 in CS) closely match nominal sizes for easy replacement of AS568-standard parts.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePack quantity:\u003c\/strong\u003e Comes as a pack of 25, which is convenient for preventive maintenance kits or repeated repairs without frequent reordering.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChemical compatibility:\u003c\/strong\u003e Performs well in petroleum, diesel, biodiesel blends, methanol\/ethanol blends, silicone oils and high vacuum applications.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eWho It's For\u003c\/h2\u003e\n\u003cp\u003eThis product suits industrial mechanics, automotive technicians and OEM maintenance staff who work with fuel systems, hydraulic lines or equipment exposed to high temperature or aggressive fluids. The combination of Viton chemistry and 90A hardness makes it a practical choice where resistance to oils, fuels and heat is required.\u003c\/p\u003e\n\u003cp\u003eIt is less suitable for applications needing very soft seals, food-grade certification, or specialized low-temperature elastomers below the stated range. Buyers requiring a different durometer or non-fluorocarbon compound should look elsewhere.\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 Viton FKM for durable sealing in aggressive environments.\u003c\/li\u003e\n\u003cli\u003e90A durometer offers a good balance of firmness and flexibility for many industrial sealing tasks.\u003c\/li\u003e\n\u003cli\u003ePack of 25 provides value for maintenance programs and reduces downtime due to reordering.\u003c\/li\u003e\n\u003cli\u003eActual and metric measurements are provided, simplifying parts matching and inventory tracking.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eCons\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eViton is not ideal for applications that require FDA food-grade elastomers or very soft seals below 90A.\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 (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\u003e4-1\/2 in ID, 4-11\/16 in OD, 3\/32 in CS\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eActual dimensions\u003c\/td\u003e\n\u003ctd\u003e4.487 in ID, 4.693 in OD, 0.103 in CS\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMetric dimensions\u003c\/td\u003e\n\u003ctd\u003e113.97 mm ID, 119.21 mm OD, 2.62 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\u003ePack quantity\u003c\/td\u003e\n\u003ctd\u003e25 pieces\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003ch2\u003eOur Verdict\u003c\/h2\u003e\n\u003cp\u003eThe Mr O-Ring 157 Viton O-Ring pack is a practical, cost-effective choice for professionals who need durable seals resistant to fuels, oils and high temperatures; the 90A durometer and accurate dimensions make it a reliable replacement for AS568 applications and a good value when bought in a pack of 25.\u003c\/p\u003e\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eAre these O-rings compatible with diesel and biodiesel blends?\u003c\/strong\u003e\u003cbr\u003eYes, Viton FKM is listed as performing well with diesel and biodiesel blend fuels and other petroleum products.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDo the sizes follow AS568 standards?\u003c\/strong\u003e\u003cbr\u003eThe product is designed to meet AS568 size standards with nominal and actual dimensions provided for verification.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat temperature range can these O-rings handle?\u003c\/strong\u003e\u003cbr\u003eThey are rated from -26C (-15F) up to 232C (450F), suitable for many high-temperature sealing tasks.\u003c\/p\u003e","brand":"Mr O-Ring","offers":[{"title":"Default Title","offer_id":48657482252507,"sku":"B07R75D149","price":54.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0724\/1043\/1707\/files\/51Kuv29LevL._SL1000_41f0be71-da0d-485d-bad9-23aa848f1dcc.jpg?v=1778728205","url":"https:\/\/gearmusthave.com\/products\/mr-o-ring-157-viton-o-ring-4-1-2-in-id-pack-of-25","provider":"GearMustHave","version":"1.0","type":"link"}