{"product_id":"210-in-silicone-o-ring-cord-stock-70a-red-25-ft","title":".210 in Silicone O-Ring Cord Stock 70A - Red, 25 ft","description":"\u003cp\u003eIn this review the.210 in silicone O-ring cord stock is evaluated for technicians and hobbyists who need a reliable, heat-resistant seal material. The bottom line: this red silicone cord is best for rebuilds and custom O-rings where temperature resilience and chemical resistance are primary concerns, and it stands out because of its consistent 70A durometer and broad usable temperature range. The cord is presented as a practical replacement or fabrication stock piece rather than a finished gasket, and the review focuses on real-world handling, resistance properties, and where it fits into workshop use.\u003c\/p\u003e\u003ch2\u003eKey Features\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Made from silicone, the cord offers reliable resistance to ozone, weather and many oils so it lasts in outdoor and automotive-adjacent uses.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTemperature range:\u003c\/strong\u003e Rated for an extensive temperature span, the cord handles very low and very high temperatures, making it suitable for extreme environment applications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDurometer:\u003c\/strong\u003e At 70A hardness the cord balances flexibility and firmness, which helps when cutting and forming replacement O-rings that must hold a seal.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCross section and size:\u003c\/strong\u003e The round.210 in nominal thickness is a consistent profile for fabricating standard size O-rings and seals from a single 25 ft piece.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChemical compatibility:\u003c\/strong\u003e Silicone resists detergents, salt water, non-petroleum brake fluid and many hydraulic fluids, providing durable sealing where those fluids are present.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOrigin:\u003c\/strong\u003e Made in the U S A, which can matter for buyers prioritizing domestic manufacturing and consistent quality control.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eWho It's For\u003c\/h2\u003e\u003cp\u003eThis cord is aimed at mechanics, maintenance techs and DIYers who need to cut custom O-rings or repair seals exposed to wide temperature swings or weathering. It is particularly useful when replacement parts are not available and a custom-sized ring is the practical option.\u003c\/p\u003e\u003cp\u003eThose who need high abrasion resistance or long-term steam exposure above 250 degrees F should consider other materials; silicone performs poorly under prolonged mechanical wear and at high-temperature steam environments.\u003c\/p\u003e\u003ch2\u003ePros \u0026amp; Cons\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003ePros\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eConsistent 70A hardness provides a good balance for cutting and seating custom O-rings.\u003c\/li\u003e\n\u003cli\u003eWide usable temperature range supports both cold and hot application points.\u003c\/li\u003e\n\u003cli\u003eGood resistance to ozone, weather and many oils reduces premature failure in outdoor and engine-area seals.\u003c\/li\u003e\n\u003cli\u003eLong 25 ft length allows multiple rings to be produced from a single piece, offering good value.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCons\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eSilicone is more vulnerable to mechanical wear and long-term steam exposure above 250 degrees F than some elastomers.\u003c\/li\u003e\n\u003cli\u003eNot fully compatible with aromatic hydrocarbons and strong acids or bases, so it is not universal.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eSpecifications\u003c\/h2\u003e\u003ctable\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaterial\u003c\/td\u003e\n\u003ctd\u003eSilicone\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNominal thickness\u003c\/td\u003e\n\u003ctd\u003e0.210 in (.210 in round)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDurometer\u003c\/td\u003e\n\u003ctd\u003e70A\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLength\u003c\/td\u003e\n\u003ctd\u003e25 ft piece\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTemperature range\u003c\/td\u003e\n\u003ctd\u003e-76 F to 437 F (-60 C to 225 C)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eColor\u003c\/td\u003e\n\u003ctd\u003eRed\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMade in\u003c\/td\u003e\n\u003ctd\u003eU S A\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003ch2\u003eOur Verdict\u003c\/h2\u003e\u003cp\u003eThe.210 in silicone O-ring cord stock is a practical, well-made option for anyone fabricating replacement O-rings where temperature range and chemical resistance to oils and weathering matter. It offers solid value in a 25 ft length and consistent 70A hardness, but buyers needing high abrasion durability or resistance to aromatic hydrocarbons should review material fit first.\u003c\/p\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eCan this cord be used for custom O-rings?\u003c\/strong\u003e\u003cbr\u003eYes. The round.210 in cross section and 70A durometer make it suitable for cutting and forming custom O-rings for many sealing needs.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat fluids is silicone resistant to?\u003c\/strong\u003e\u003cbr\u003eSilicone resists ozone, weather, detergents, salt water, engine and transmission oil, non-petroleum brake fluid and certain hydraulic fluids, but it is vulnerable to aromatic and some chlorinated hydrocarbons.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs this cord suitable for steam service?\u003c\/strong\u003e\u003cbr\u003eSilicone performs poorly with prolonged steam exposure above 250 degrees F, so it is not recommended for long-term steam sealing at high temperatures.\u003c\/p\u003e","brand":"Mr O-Ring","offers":[{"title":"Default Title","offer_id":48230138970331,"sku":"B00QVAZTFY","price":47.29,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0724\/1043\/1707\/files\/71AOKKbdBAL._SL1500_9bc8d315-0cd2-477e-9d26-81dbfa1206a0.jpg?v=1770744976","url":"https:\/\/gearmusthave.com\/products\/210-in-silicone-o-ring-cord-stock-70a-red-25-ft","provider":"GearMustHave","version":"1.0","type":"link"}