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    2 Products
    About O-Rings
    industrial info icon

    Find the right size, compare compatible materials, and choose the best cross section shape for your O-ring.

    PTFE Backup Ring Assortments

    Image of Product. Front orientation. Backup Rings. PTFE Backup Ring Assortments.
    These 325-piece assortments mean you’ll always have a backup ring on hand. Use them to extend the life of your O-rings and improve their performance in high-pressure applications. The backup rings are made of PTFE and resist harsh chemicals such as, acetone, fluorinated solvents, methanol, and many acids.
    No. of
    Pieces
    No. of
    Sizes
    Includes
    Hardness
    Temp. Range,
    ° F
    Color
    Each
    32536Dash Numbers 005-018, 110-121, 210-219Durometer 55D (Hard)-100 to 500White9560K150000000
     

    Buna-N Backup Ring Assortments

    Image of Product. Front orientation. Backup Rings. Buna-N Backup Ring Assortments.
    Always have the backup ring you need for oily equipment operating at pressures up to 2,500 psi. These rings support O-rings to extend their life and prevent them from deforming under pressure, which can cause pressure loss. Made of Buna-N, they won’t swell when exposed to grease, petroleum fluids, and motor oil. However, they will degrade when exposed to mild or harsh chemicals. They’re often used in hydraulic and automotive systems.
    No. of
    Pieces
    No. of
    Sizes
    Includes
    Max. Pressure,
    psi
    Specs.
    Met
    Temp. Range,
    ° F
    Hardness
    Color
    Each
    29336Dash Numbers 005-018, 110-121, 210-2192,500ASTM D2000-30 to 250Durometer 90A (Hard)Black93985K33000000
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