470 Viton O-Ring 75A Durometer, 21 in ID - Durable Chemical Seal

In this review the 470 Viton O-Ring is assessed as a single-purpose replacement seal for demanding environments; the bottom line is that it is best for technicians, hobbyists, and mechanics who need a chemically resistant, heat-tolerant O-ring that conforms to standard aerospace sizes. The reviewer found the O-ring's main selling point is its material: brown Viton with a 75A durometer provides reliable resistance to fuels, oils, and many solvents while maintaining shape across a very wide temperature range.

Key Features

• Material: Viton fluorocarbon elastomer offers high heat and chemical resistance for use with fuels, oils, and many solvents.
• Hardness: 75A durometer gives a firm profile that resists penetration and holds a seal under compression in dynamic or static applications.
• Shape: Round cross-section delivers a dependable seal between cylindrical overlapping surfaces like injectors and hose fittings.
• Temperature range: Rated from -15 degrees F to 400 degrees F so it performs in both low-temperature storage and high-heat operating conditions.
• Standard sizing: Manufactured to the aerospace size standard AS568A so it fits common industry grooves and replacement applications.

Who It's For

This O-ring is ideal for professionals and DIYers replacing seals on engines, hydraulic fittings, garden hose adapters, or equipment exposed to fuels and hydrocarbons; anyone who needs a compact, chemically resistant seal will appreciate its compatibility with non-flammable hydraulic fuels, silicone oil, and many hydrocarbons. The standard AS568A sizing means it is useful where exact aerospace-size replacements are required.

It is less appropriate for applications exposed to low molecular weight organic acids, ammonia gas, strong alkalis, or certain amines, since Viton is vulnerable to those chemicals. Also, projects that require a softer, thicker cross-section or a different color match may want to consider alternative elastomers.

Pros & Cons

Pros

• Excellent heat and fuel resistance from the Viton material for long service life in harsh conditions.
• Firm 75A hardness maintains a secure seal and resists extrusion under compression.
• AS568A sizing and round profile make it an easy replacement for common cylinder and hose fittings.
• Customers report good fit and leak prevention in engine injectors and hose applications, supporting real-world reliability.

Cons

• Vulnerable to certain chemicals such as low molecular organic acids, ammonia, and strong alkalis, limiting compatibility in some chemical systems.
• Some users noted the ring felt thinner than expected for specific uses, so verify cross-section thickness against your groove before relying on it for high-pressure sealing.

Specifications

Material	Viton (fluorocarbon elastomer)
Durometer	75A
Cross-section	Round
Inner diameter (ID)	21 in
Outer diameter (OD)	21-1/2 in
Width	1/4 in
Temperature range	-15 degrees F to 400 degrees F (-26 degrees C to 205 degrees C)

Our Verdict

The 470 Viton O-Ring is a solid choice when chemical resistance and high-temperature durability matter; its 75A durometer and AS568A sizing make it a reliable replacement for engine injectors, hose fittings, and many sealing tasks. It represents good value for users who need long-lasting seals in fuel and hydrocarbon environments, provided the chemical compatibility and thickness meet the application's needs.

Frequently Asked Questions

Is this O-ring compatible with gasoline and diesel?
Yes, Viton is compatible with many fuels and aromatic and aliphatic hydrocarbons, making it suitable for gasoline and diesel sealing in most cases.

What temperature range will this seal tolerate?
The O-ring is rated from -15 degrees F (-26 degrees C) up to 400 degrees F (205 degrees C), covering most automotive and industrial applications.

Will it fit standard grooves and parts?
Yes, it conforms to the AS568A aerospace size standard so it will fit common industry grooves and standard replacement slots.