Mr O-Ring 011 Viton O-Ring 90A Durometer 5/16in ID - Pack of 1000

In this review the Mr O-Ring 011 Viton O-Ring is evaluated for mechanics, technicians and maintenance buyers who need a durable, high-temperature seal in quantity. The bottom line: this pack of 1000 90A durometer Viton o-rings is best for applications exposed to fuels, oils, high heat or ozone where chemical resistance matters, and its wide temperature range and Viton compound make it a reliable, long-lasting choice for routine rebuilds and production spares.

Key Features

• Material: Viton (fluorocarbon FKM) offers strong resistance to fuels, mineral oils and many organic solvents, reducing seal failure in chemically aggressive fluids.
• Durometer: 90A hardness provides a firm seal that resists extrusion and maintains shape across a broad service range.
• Temperature range: Rated from -26C to 232C (-15F to 450F), allowing use in high temperature engines and hot process lines without rapid degradation.
• Quantity: Pack of 1000 supplies workshops and production runs, cutting downtime by keeping common sizes on hand.
• Dimensions: Nominal 5/16in ID, 7/16in OD, 1/16in CS with actual measured dimensions for tighter tolerance planning.
• Standards: Sized to the AS568 standard, making it easy to replace common specification o-rings in industrial and OEM equipment.

Who It's For

This product is aimed at maintenance technicians, small manufacturers and hobbyists who service engines, pumps, or fittings exposed to petroleum, diesel, biodiesel blends, methanol or ethanol blends, and many hydraulic fluids. The bulk pack is practical for shops that consume large volumes of a common AS568 size and need a compound that endures heat and chemical exposure.

Those who should look elsewhere include users needing very soft, low-durometer seals for low-pressure sealing or extreme low-temperature flexibility, and customers seeking non-Viton elastomers specifically rated for steam or specific food-grade approvals not claimed here.

Pros & Cons

Pros

• Excellent chemical resistance to fuels, oils and many solvents, extending service life in aggressive fluids.
• High temperature capability up to 232C (450F) suits demanding thermal environments.
• Bulk pack of 1000 ensures ready supply for workshops and saves on frequent reordering.
• AS568 sizing and known actual dimensions make replacements predictable and less likely to leak from fit errors.

Cons

• Higher durometer (90A) may be too stiff for applications needing very soft sealing or very low-temperature flexibility.

Specifications

Brand	Mr O-Ring
Material	Viton (FKM)
Durometer	90A
Nominal dimensions	5/16in ID x 7/16in OD x 1/16in CS
Actual dimensions	0.301in ID x 0.441in OD x 0.070in CS
Temperature range	-26C (-15F) to 232C (450F)
Pack quantity	1000

Our Verdict

The Mr O-Ring 011 Viton 90A in a 1000-piece pack is a solid choice for shops and manufacturers that need a chemically resistant, high-temperature AS568 o-ring in volume. It delivers dependable sealing performance where petroleum, biodiesel blends and high heat are present, and the bulk pack offers practical value for routine maintenance and production spares.

Frequently Asked Questions

Are these o-rings suitable for gasoline and diesel fuel?
Yes, Viton FKM is formulated to resist petroleum products including gasoline, diesel and many fuel blends, making these o-rings suitable for fuel system seals.

Will the 90A hardness work for high temperature engine seals?
Yes, the 90A durometer combined with a rated temperature up to 232C (450F) makes them appropriate for many high temperature engine and equipment sealing points.

Do these o-rings meet a standard size?
They follow AS568 size conventions with nominal and actual dimensions provided for reliable replacement sizing.