M5x70 Viton O-Ring, 75A Durometer, 70 mm ID - Durable Seal

In this review the M5x70 Viton O-Ring is evaluated for technicians and hobbyists who need a reliable, chemical-resistant seal. The bottom line: this pack of 10 black Viton O-rings stands out for chemical and heat resistance, making it the best pick when compatibility with fuels, oils and hydrocarbons matters most. The reviewer found the O-ring's 75A durometer and round cross-section provide a firm, long-lasting seal for threaded barrels, carburetor seats and other cylindrical overlaps while remaining flexible across a wide temperature range.

Key Features

• Material: Made from Viton fluorocarbon elastomer to resist fuels, oils and many chemicals so it lasts in demanding environments.
• Hardness: 75A durometer offers a balance of flexibility and firmness that maintains a reliable seal without extruding under pressure.
• Temperature range: Rated for wide temperature use so it performs from cold starts through high-heat operating conditions.
• Design: Round cross-section creates a consistent seal between cylindrical overlapping surfaces for thread protection and seat sealing.
• Compatibility: Works well with non-flammable hydraulic fuels, silicone oil and aromatic and aliphatic hydrocarbons, giving broad application options.

Who It's For

This O-ring is ideal for mechanics, small engine users, and industrial service techs who need a compact, chemical-resistant seal for threaded barrels, carburetor seats, and similar applications. The pack of 10 suits maintenance tasks where multiple replacements or spares are useful.

Users who need compatibility with strong acids, ammonia gas, alkalis or glycol-based brake fluids should look elsewhere or confirm compatibility, as Viton can be vulnerable to some low molecular weight organic acids and ammonia.

Pros & Cons

Pros

• Good chemical resistance for fuels and many solvents, reducing replacement frequency.
• 75A durometer gives a dependable seal while remaining flexible enough for thread protection and seat use.
• Pack of 10 provides value for maintenance and multiple applications.
• Works across a broad temperature range, suitable for many automotive and industrial settings.

Cons

• Not compatible with ammonia, some alkalis and certain organic acids, so it is not universal for all fluids.
• The higher temperature limit noted in some specs may vary by compound; confirm for extreme steam or caustic exposures.

Specifications

Our Verdict

The M5x70 Viton O-Ring is a practical, value-focused choice for anyone needing a resilient seal against fuels and common solvents. It is best for threaded barrels, carburetor seats and other cylindrical seals where chemical and heat resistance matter; just avoid environments with ammonia or strong alkalis.

Frequently Asked Questions

Is this O-ring compatible with gasoline?
Yes, Viton is compatible with many fuels and hydrocarbons, making this O-ring suitable for gasoline-contact applications.

What temperature range will it tolerate?
It is intended for wide temperature use, performing from below freezing up to several hundred degrees Fahrenheit in typical service.

How many O-rings are included?
The product comes as a pack of 10 identical Viton O-rings.