Best O-Rings for Heat-Resistant Sealing (2026)

• 3 products compared from 1 brand • avg ItemOracle score 4.2/5

We prioritized fluoroelastomer (Viton) construction, commonly used durometer (75A), accurate listed dimensions, and pack value for heat-resistant sealing needs

The Verdict

Top Picks

  1. 1
    O-Ring, Viton, 75A, 3" ID x 3.5" OD, 1/4" 5-pack

    Best Overall O-Ring, Viton, 75A, 3" ID x 3.5" OD, 1/4" 5-pack

    Mr O-Ring • ★ 4.2/5 • Budget

    Best fit for medium seals: 75A Viton in a 3" ID x 3.5" OD size offering a balanced durometer for heat sealing

    Viton O-rings with 75A hardness for chemical and fuel compatibility. Round cross-section provides a seal between cylindrical surfaces across a wide temperature range. Customers note precise fit and reliable performance in heat and replacement applications

    • Viton elastomer
    • 75A durometer
    • AS568A conformity
    Check current price on Amazon →
  2. 2
    251 Viton O-Ring 75A 5-1/8" ID 5-3/8" OD 1/8" W (pack of 10)

    Best Value 251 Viton O-Ring 75A 5-1/8" ID 5-3/8" OD 1/8" W (pack of 10)

    Mr O-Ring • ★ 4.2/5 • Budget

    Best for larger-gland replacements: 5-1/8" ID 75A Viton O-rings in a multi-pack designed for heat-resistant service

    Viton O-ring with 75A durometer for sealing between cylindrical surfaces. Wide temperature range and chemical compatibility. Customers note precise fit and reliable leak resistance

    • Viton chemical and fuel compatibility
    • 75A durometer for durability
    • AS568A standard compliance
    Check current price on Amazon →
  3. 3
    Viton O-Ring 75A 5-1/4" ID 5-1/2" OD 1/8" Width (Pack of 10)

    Viton O-Ring 75A 5-1/4" ID 5-1/2" OD 1/8" Width (Pack of 10)

    Mr O-Ring • ★ 4.2/5 • Budget

    Best for slightly larger ID needs: 5-1/4" ID 75A Viton O-rings in packs that simplify repeated maintenance

    Viton O-ring with 75A durometer for chemical and fuel compatibility. Round cross-section for sealing between cylindrical surfaces and broad temperature range. Customer note: fits well and remains leak-resistant

    • Viton material for chemical resistance
    • 75A durometer for durable seals
    • AS568A standards compatibility
    Buy at Amazon →

Buying Guide

Choose the right material

Select fluoroelastomer (Viton) for heat and chemical resistance common in high-temperature sealing

Match inner diameter and cross-section

Pick an O-ring with an ID and width that match the gland to ensure proper compression and sealing performance

Consider durometer hardness

75A durometer provides a balance of elasticity and compression set resistance for many heat-sealing applications

Check size tolerance and pack quantity

Larger packs or multi-packs reduce downtime; confirm the listed ID/OD and width matches your replacement needs

Assess chemical compatibility

Verify the O-ring's fluoroelastomer compatibility with your fluids and operating temperatures to avoid swelling or degradation