Mr O-Ring 377 Viton O-Ring 90A Durometer 10in ID Pack of 10

In this review the Mr O-Ring 377 Viton O-Ring pack is judged for technicians and maintenance teams who need a reliable, high-temperature sealing option. The bottom line: these 90A durometer Viton rings are best for applications exposed to fuels, oils and high heat where chemical resistance matters most. The review finds the pack of 10 an economical choice for routine replacement and preventive maintenance because the material resists petroleum products, biodiesel blends, silicone oils and ozone throughout a wide operating range.

Key Features

• Material: Fluorocarbon rubber (Viton/FKM) provides broad chemical resistance so seals last longer in fuel and oil environments.
• Durometer: The 90A hardness offers a firm seal that resists extrusion and maintains shape under compression for many static and low-dynamic applications.
• Temperature range: Rated from -26C to 232C so these o-rings suit both cold storage and very high temperature service without rapid degradation.
• Size accuracy: Actual dimensions (9.975in ID, 10.395in OD, 0.210in CS) match nominal sizing needs for predictable replacement in AS568 specified housings.
• Pack size: Supplied as a pack of 10 which is convenient for small crews and scheduled preventative maintenance without buying excess stock.
• Versatility: Performs well with petroleum, methanol or ethanol blends, diesel and biodiesel, and in high vacuum or ozone-exposed systems.

Who It's For

This product suits industrial maintenance crews, HVAC and plumbing technicians, and small fabrication shops that require o-rings resistant to fuels, hydraulic fluids and high temperatures. The firm 90A durometer is useful where a durable, tight seal is needed rather than a very soft gasket.

It is not ideal for sealing applications that require very soft, highly flexible elastomers (for example low-pressure dynamic shaft seals with heavy flexing) or situations that mandate a different rubber family for compatibility with a specific solvent not listed here.

Pros & Cons

Pros

• Excellent chemical and temperature resistance thanks to the Viton (FKM) compound.
• Pack of 10 provides value for scheduled maintenance and repeat replacements.
• Accurate actual dimensions reduce the guesswork when matching AS568 sizes for replacement.

Cons

• The 90A hardness may be too firm for some dynamic sealing applications that require softer compounds for flexibility.

Specifications

Material	Viton (FKM)
Durometer	90A
Nominal dimensions	10in ID, 10-3/8in OD, 3/16in CS
Actual dimensions	9.975in ID, 10.395in OD, 0.210in CS
Metric dimensions	253.37 mm ID, 264.03 mm OD, 5.33 mm CS
Temperature range	-26C to 232C (-15F to 450F)
Pack quantity	10 rings

Our Verdict

The Mr O-Ring 377 Viton 90A o-ring pack is a sensible buy for technicians who need a compact supply of high-temperature, chemically resistant seals. It offers good dimensional accuracy and broad media compatibility, making it a practical, cost-effective choice for fuel, oil and high-heat sealing tasks while remaining less suitable where very soft elastomer behavior is required.

Frequently Asked Questions

Are these o-rings suitable for fuel blends?
Yes. The Viton compound performs well with petroleum, methanol or ethanol blends, diesel and biodiesel according to the product description.

What temperature range will they tolerate?
They are rated from -26C (-15F) up to 232C (450F), suitable for cold and very high temperature applications.

Do the rings match standard AS568 sizes?
The product meets size standards defined by AS568 and provides actual dimensions for accurate replacement.