350 Viton O-Ring 75A 4-5/8in ID 5in OD Pack of 10 - Chemical & Heat

In this review the 350 Viton O-Ring is evaluated for technicians, hobbyists, and maintenance pros who need a reliable seal for fuel, chemical, and high-temperature applications. The bottom line is that this pack of ten Viton o-rings delivers consistent fit and broad chemical compatibility, making it a practical replacement option where resistance to fuels, aromatic and aliphatic hydrocarbons, and high temperatures matters. The review focuses on build material, usable temperature range, durometer, and common uses that customers report, so readers can decide quickly if these are suitable for their sealing jobs.

Key Features

• Material: Made of Viton fluorocarbon elastomer, these o-rings resist many fuels and chemicals for longer service life.
• Temperature range: Rated from -15 degrees F to 400 degrees F, the o-rings handle high-heat engine and industrial environments without rapid degradation.
• Hardness: The 75A shore durometer provides good resistance to penetration while remaining flexible enough for effective sealing on cylindrical surfaces.
• Cross-section: Round profile creates a reliable seal between overlapping cylindrical parts such as bottles, barrels, and fittings.
• Compatibility: Suitable with non-flammable hydraulic fuels, silicone oils, chlorinated hydrocarbons, aromatic and aliphatic hydrocarbons, and vacuum or ozone-exposed systems.
• Standards: Manufactured to meet the dimensions and interchangeability expected of common aerospace-style o-ring standards.

Who It's For

This pack is ideal for professionals and serious DIYers replacing seals on fuel bottles, solvent-handling equipment, weapon accessories where appropriate, and other systems exposed to fuels, oils, and high heat. Customers who value leak resistance and consistent sizing will appreciate having ten identical rings on hand for maintenance cycles.

It is not the best choice for environments dominated by low molecular organic acids, ammonia gas, strong alkalis, amines, glycol-based brake fluids, or super-heated steam, as Viton is vulnerable to those chemicals and conditions. For those specific chemistries users should look for alternative elastomers.

Pros & Cons

Pros

• Excellent heat and fuel resistance makes these o-rings durable in high-temperature and fuel-exposed applications.
• Consistent sizing and round cross-section result in a reliable, leak-resistant seal for cylindrical parts.
• Good value as a pack of ten for routine replacement and spares, as customers report fit and functionality for several common uses.
• Compatible with a wide list of hydrocarbons and many industrial fluids, offering broad utility.

Cons

• Not compatible with low molecular organic acids, ammonia, alkalis, amines, glycol-based brake fluids, or super-heated steam, so chemical compatibility must be checked first.
• The 75A hardness may be firmer than needed for very low-pressure sealing where a softer compound would perform better.

Specifications

Material	Viton (fluorocarbon elastomer)
Color	Black
Inner diameter (ID)	4-5/8 in
Outer diameter (OD)	5 in
Cross-section / Width	3/16 in
Durometer	75A shore
Temperature range	-15 degrees F to 400 degrees F (-26 C to 205 C)

Our Verdict

The 350 Viton O-Ring pack is a solid, cost-effective choice for service technicians and hobbyists who need reliable seals resistant to fuels, aromatic and aliphatic hydrocarbons, and heat. Its 75A hardness and Viton compound deliver durable performance where chemical compatibility is appropriate, making this pack good value for routine maintenance and replacements.

Frequently Asked Questions

Are these o-rings suitable for fuel-exposed seals?
Yes, Viton is compatible with many fuels, aromatic and aliphatic hydrocarbons, and non-flammable hydraulic fuels, making these o-rings suitable for many fuel-exposed seals.

What temperature range will they tolerate?
They are acceptable from -15 degrees F (-26 C) up to 400 degrees F (205 C), covering most heat-exposed applications short of super-heated steam.

Will they work with brake fluids or ammonia?
No, Viton is vulnerable to glycol-based brake fluids, ammonia gas, low molecular organic acids, and strong alkalis, so use an alternate elastomer for those chemicals.