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    54 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.

    Oil-Resistant Buna-N Backup Rings

    Image of ProductInUse. O-Ring Sealing Properly with Backup Ring. Front orientation. CrossSection view. Contains Annotated. Backup Rings. Oil-Resistant Buna-N Backup Rings.
    Image of ProductInUse. O-Ring Deforms Without a Backup Ring. Front orientation. CrossSection view. Contains Annotated. Backup Rings. Oil-Resistant Buna-N Backup Rings.

    O-Ring Sealing Properly with

    Backup Ring

    O-Ring Deforms Without a Backup Ring

    Image of Product. Bottom orientation. Backup Rings. Oil-Resistant Buna-N Backup Rings.
    Image of Attribute. Front orientation. CrossSection view. Contains Annotated. Oil-Resistant Buna-N Backup Rings.
    Extend the life of O-rings in oily, high-pressure systems that operate at up to 2,500 psi. These backup rings support O-rings and prevent them from deforming under pressure and causing pressure loss. Made of Buna-N, these rings 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, automotive, and industrial systems. All have a shelf life, cure date, and a traceable lot number printed on the bag.
    Pkg.
    For Dash
    No.
    Thk.
    ID
    OD
    Hardness
    Temp. Range,
    ° F
    Color
    Pkg.
    Qty.
    1-9
    10-Up
    0.053" Wide
    004
    		0.049"0.096"0.202"Durometer 90A (Hard)-30 to 250Black1005288T110000000000
    005
    		0.049"0.127"0.233"Durometer 90A (Hard)-30 to 250Black1005288T11100000000
    006
    		0.049"0.140"0.246"Durometer 90A (Hard)-30 to 250Black1005288T11200000000
    007
    		0.049"0.171"0.277"Durometer 90A (Hard)-30 to 250Black1005288T11300000000
    008
    		0.049"0.202"0.308"Durometer 90A (Hard)-30 to 250Black1005288T11400000000
    009
    		0.049"0.234"0.340"Durometer 90A (Hard)-30 to 250Black1005288T11500000000
    010
    		0.049"0.265"0.371"Durometer 90A (Hard)-30 to 250Black1005288T11600000000
    011
    		0.049"0.327"0.433"Durometer 90A (Hard)-30 to 250Black1005288T11700000000
    012
    		0.049"0.390"0.496"Durometer 90A (Hard)-30 to 250Black1005288T11800000000
    013
    		0.049"0.455"0.561"Durometer 90A (Hard)-30 to 250Black1005288T11900000000
    014
    		0.049"0.518"0.624"Durometer 90A (Hard)-30 to 250Black1005288T1200000000
    015
    		0.049"0.580"0.686"Durometer 90A (Hard)-30 to 250Black1005288T12100000000
    016
    		0.049"0.643"0.749"Durometer 90A (Hard)-30 to 250Black1005288T12200000000
    017
    		0.049"0.705"0.811"Durometer 90A (Hard)-30 to 250Black1005288T12300000000
    018
    		0.049"0.768"0.874"Durometer 90A (Hard)-30 to 250Black1005288T12400000000
    019
    		0.049"0.830"0.936"Durometer 90A (Hard)-30 to 250Black1005288T12500000000
    020
    		0.049"0.893"0.999"Durometer 90A (Hard)-30 to 250Black1005288T12600000000
    021
    		0.049"0.955"1.061"Durometer 90A (Hard)-30 to 250Black1005288T12700000000
    022
    		0.049"1.018"1.124"Durometer 90A (Hard)-30 to 250Black1005288T12800000000
    023
    		0.049"1.08"1.186"Durometer 90A (Hard)-30 to 250Black1005288T12900000000
    024
    		0.049"1.143"1.249"Durometer 90A (Hard)-30 to 250Black1005288T1300000000
    025
    		0.049"1.205"1.311"Durometer 90A (Hard)-30 to 250Black1005288T131000000000
    026
    		0.049"1.268"1.374"Durometer 90A (Hard)-30 to 250Black1005288T132000000000
    027
    		0.049"1.33"1.436"Durometer 90A (Hard)-30 to 250Black1005288T1330000000000
    028
    		0.049"1.393"1.499"Durometer 90A (Hard)-30 to 250Black1005288T1340000000000
    029
    		0.049"1.518"1.624"Durometer 90A (Hard)-30 to 250Black1005288T1350000000000
    030
    		0.049"1.643"1.749"Durometer 90A (Hard)-30 to 250Black1005288T1360000000000
    031
    		0.049"1.768"1.874"Durometer 90A (Hard)-30 to 250Black1005288T1370000000000
    042
    		0.049"3.268"3.374"Durometer 90A (Hard)-30 to 250Black505288T1480000000000
     

    Ultra-Chemical-Resistant PTFE Backup Rings

    Image of Product. Front orientation. Backup Rings. Ultra-Chemical-Resistant PTFE Backup Rings.
    Image of Attribute. Front orientation. CrossSection view. Contains Annotated. Ultra-Chemical-Resistant PTFE Backup Rings.
    These PTFE backup rings resist harsh chemicals, such as acetone, fluorinated solvents, methanol, and many acids. Use them to extend the life of your O-rings and improve their performance in high-pressure applications.
    For Dash
    No.
    Thk.
    ID
    OD
    Hardness
    Temp. Range,
    ° F
    Color
    Pkg.
    Qty.
    Pkg.
    0.053" Wide
    005
    		0.049"0.124"0.230"Durometer 55D (Hard)-300 to 500White509560K31000000
    006
    		0.049"0.140"0.246"Durometer 55D (Hard)-300 to 500White509560K3200000
    007
    		0.049"0.171"0.277"Durometer 55D (Hard)-300 to 500White509560K3300000
    008
    		0.049"0.202"0.308"Durometer 55D (Hard)-300 to 500White509560K3400000
    009
    		0.049"0.234"0.340"Durometer 55D (Hard)-300 to 500White509560K3500000
    010
    		0.049"0.265"0.371"Durometer 55D (Hard)-300 to 500White509560K3600000
    011
    		0.049"0.327"0.433"Durometer 55D (Hard)-300 to 500White509560K3700000
    012
    		0.049"0.390"0.496"Durometer 55D (Hard)-300 to 500White509560K3800000
    013
    		0.049"0.455"0.561"Durometer 55D (Hard)-300 to 500White509560K3900000
    014
    		0.049"0.518"0.624"Durometer 55D (Hard)-300 to 500White509560K4100000
    015
    		0.049"0.580"0.686"Durometer 55D (Hard)-300 to 500White509560K4200000
    016
    		0.049"0.643"0.749"Durometer 55D (Hard)-300 to 500White509560K4300000
    017
    		0.049"0.705"0.811"Durometer 55D (Hard)-300 to 500White509560K4400000
    018
    		0.049"0.768"0.874"Durometer 55D (Hard)-300 to 500White509560K4500000
    019
    		0.049"0.801"0.907"Durometer 55D (Hard)-300 to 500White509560K10100000
    020
    		0.049"0.864"0.970"Durometer 55D (Hard)-300 to 500White509560K10200000
    021
    		0.049"0.926"1.032"Durometer 55D (Hard)-300 to 500White509560K10300000
    022
    		0.049"0.989"1.095"Durometer 55D (Hard)-300 to 500White509560K10400000
    024
    		0.049"1.114"1.220"Durometer 55D (Hard)-300 to 500White259560K10500000
    025
    		0.049"1.176"1.282"Durometer 55D (Hard)-300 to 500White259560K10600000
    026
    		0.049"1.239"1.345"Durometer 55D (Hard)-300 to 500White259560K10700000
    028
    		0.049"1.364"1.470"Durometer 55D (Hard)-300 to 500White259560K10800000
    029
    		0.049"1.489"1.595"Durometer 55D (Hard)-300 to 500White259560K10900000
    031
    		0.049"1.739"1.845"Durometer 55D (Hard)-300 to 500White109560K11100000
     

    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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