Mr O-Ring 448 Viton O-Ring 90A Durometer 9-1/2in ID - Durable Seal

In this review the Mr O-Ring 448 Viton O-Ring is presented as a straightforward replacement seal for demanding applications; it is best for technicians, maintenance pros, and hobbyists who need a heat- and chemical-resistant o-ring in the AS568 size range. The single biggest reason to buy is its high-performance Viton (FKM) compound with a 90A durometer that resists fuels, oils, ozone and high temperatures up to 232C, making it a reliable choice where lesser elastomers fail.

Key Features

• Material: Viton (fluorocarbon rubber) delivers wide chemical resistance for use with petroleum products, fuels, mineral oils and many organic solvents.
• Temperature range: Rated from -26C to 232C, it tolerates very high operating temperatures and maintains seal integrity where heat resistance is required.
• Hardness: The 90A durometer provides a firm, durable seal that resists extrusion and deformation under pressure.
• Size accuracy: Nominal and actual dimensions are closely matched (9-1/2in ID nominal, actual 9.475in ID) for reliable interchange into AS568-compliant grooves and hardware.
• Versatility: Performs well in environments including high vacuum, ozone, weathering and when exposed to alcohol blends like methanol or ethanol.
• Shelf-life: Essentially unlimited shelf-life makes it practical to keep spares on hand without concern for material aging.

Who It's For

This o-ring is aimed at maintenance technicians, industrial users and DIYers who need a single, dependable seal that resists fuels, oils and elevated temperatures. Its AS568-compliant sizing and tight actual dimensions make it suitable for replacing worn seals in pumps, fuel systems, hydraulic equipment and high-temp enclosures.

Those who need softer sealing compounds for very low-pressure or softer-mating surfaces should consider lower durometer elastomers, and users with specific food-grade or medical certifications should confirm compatibility since this is an industrial Viton FKM product.

Pros & Cons

Pros

• Excellent chemical and heat resistance, suitable for fuels, oils and high-temp applications.
• Firm 90A durometer reduces risk of extrusion and provides long-term sealing under pressure.
• Accurate actual dimensions (9.475in ID, 10.025in OD) fit AS568 size expectations for straightforward replacement.
• Unlimited shelf-life means spares remain usable without special storage concerns.

Cons

• The 90A hardness may be too stiff for delicate or ultra-low-pressure seals that require a softer material.
• Not positioned as a certified food- or medical-grade product; users with those needs should verify suitability.

Specifications

Brand	Mr O-Ring
Material	Viton (FKM)
Durometer	90A
Nominal dimensions	9-1/2in ID, 10in OD, 1/4in CS
Actual dimensions	9.475in ID, 10.025in OD, 0.275in CS
Temperature range	-26C (-15F) to 232C (450F)
Shelf-life	Unlimited

Our Verdict

For anyone needing a durable, high-temperature replacement o-ring in the AS568 size range, the Mr O-Ring 448 Viton 90A is a sensible choice. Its combination of chemical resistance, accurate sizing and firm durometer makes it good value for industrial and maintenance use where longevity and heat tolerance matter.

Frequently Asked Questions

Is this o-ring compatible with gasoline and diesel?
Yes, the Viton FKM compound is formulated to resist petroleum products including gasoline, diesel and many fuel blends.

Will the 90A hardness work for hydraulic applications?
The 90A durometer provides a firm seal that is suitable for many hydraulic and high-pressure uses, though very low-pressure systems may prefer a softer compound.

Are the dimensions exact for replacement?
The actual dimensions are listed (9.475in ID, 10.025in OD, 0.275in CS) and closely match the nominal 9-1/2in ID size for reliable interchange.