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    164 Products

    Oil-Resistant Buna-N Backup Rings
    3D CAD models available

    Image of Product. Front orientation. Backup Rings. Oil-Resistant Buna-N Backup Rings.
    Image of Attribute. Front orientation. CrossSection view. Contains Annotated. Oil-Resistant Buna-N Backup Rings.
    Made of Buna-N, these backup rings resist grease, petroleum fluids, and motor oil. 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
    004
    		0.049"0.096"0.202"Durometer 90A (Hard)-40 to 250Black100000000000000
    005
    		0.049"0.127"0.233"Durometer 90A (Hard)-40 to 250Black100000000000000
    006
    		0.049"0.140"0.246"Durometer 90A (Hard)-40 to 250Black100000000000000
    007
    		0.049"0.171"0.277"Durometer 90A (Hard)-40 to 250Black100000000000000
    008
    		0.049"0.202"0.308"Durometer 90A (Hard)-40 to 250Black100000000000000
    009
    		0.049"0.234"0.340"Durometer 90A (Hard)-40 to 250Black100000000000000
    010
    		0.049"0.265"0.371"Durometer 90A (Hard)-40 to 250Black100000000000000
    011
    		0.049"0.327"0.433"Durometer 90A (Hard)-40 to 250Black100000000000000
    012
    		0.049"0.390"0.496"Durometer 90A (Hard)-40 to 250Black100000000000000
    013
    		0.049"0.455"0.561"Durometer 90A (Hard)-40 to 250Black100000000000000
    014
    		0.049"0.518"0.624"Durometer 90A (Hard)-40 to 250Black10000000000000
    015
    		0.049"0.580"0.686"Durometer 90A (Hard)-40 to 250Black100000000000000
    016
    		0.049"0.643"0.749"Durometer 90A (Hard)-40 to 250Black100000000000000
    017
    		0.049"0.705"0.811"Durometer 90A (Hard)-40 to 250Black100000000000000
    018
    		0.049"0.768"0.874"Durometer 90A (Hard)-40 to 250Black100000000000000
    019
    		0.049"0.830"0.936"Durometer 90A (Hard)-40 to 250Black100000000000000
    020
    		0.049"0.893"0.999"Durometer 90A (Hard)-40 to 250Black100000000000000
    021
    		0.049"0.955"1.061"Durometer 90A (Hard)-40 to 250Black100000000000000
    022
    		0.049"1.018"1.124"Durometer 90A (Hard)-40 to 250Black100000000000000
    024
    		0.049"1.143"1.249"Durometer 90A (Hard)-40 to 250Black10000000000000
    025
    		0.049"1.205"1.311"Durometer 90A (Hard)-40 to 250Black100000000000000
    026
    		0.049"1.268"1.374"Durometer 90A (Hard)-40 to 250Black100000000000000
    028
    		0.049"1.393"1.499"Durometer 90A (Hard)-40 to 250Black100000000000000
    029
    		0.049"1.518"1.624"Durometer 90A (Hard)-40 to 250Black100000000000000
    031
    		0.049"1.768"1.874"Durometer 90A (Hard)-40 to 250Black1000000000000000
    042
    		0.049"3.268"3.374"Durometer 90A (Hard)-40 to 250Black500000000000000
     
    0.086" Wide
    103
    		0.053"0.109"0.281"Durometer 90A (Hard)-40 to 250Black100000000000000
    109
    		0.053"0.327"0.499"Durometer 90A (Hard)-40 to 250Black100000000000000
    110
    		0.053"0.390"0.562"Durometer 90A (Hard)-40 to 250Black100000000000000
    111
    		0.053"0.452"0.624"Durometer 90A (Hard)-40 to 250Black100000000000000
    112
    		0.053"0.515"0.687"Durometer 90A (Hard)-40 to 250Black100000000000000
    113
    		0.053"0.577"0.749"Durometer 90A (Hard)-40 to 250Black100000000000000
    114
    		0.053"0.640"0.812"Durometer 90A (Hard)-40 to 250Black100000000000000
    115
    		0.053"0.702"0.874"Durometer 90A (Hard)-40 to 250Black10000000000000
    116
    		0.053"0.765"0.937"Durometer 90A (Hard)-40 to 250Black100000000000000
    117
    		0.053"0.831"1.003"Durometer 90A (Hard)-40 to 250Black100000000000000
    118
    		0.053"0.893"1.065"Durometer 90A (Hard)-40 to 250Black100000000000000
    119
    		0.053"0.956"1.128"Durometer 90A (Hard)-40 to 250Black100000000000000
    120
    		0.053"1.018"1.190"Durometer 90A (Hard)-40 to 250Black100000000000000
    121
    		0.053"1.081"1.253"Durometer 90A (Hard)-40 to 250Black100000000000000
    124
    		0.053"1.268"1.440"Durometer 90A (Hard)-40 to 250Black100000000000000
    125
    		0.053"1.331"1.503"Durometer 90A (Hard)-40 to 250Black10000000000000
    126
    		0.053"1.393"1.565"Durometer 90A (Hard)-40 to 250Black100000000000000
    128
    		0.053"1.518"1.690"Durometer 90A (Hard)-40 to 250Black1000000000000000
    130
    		0.053"1.643"1.815"Durometer 90A (Hard)-40 to 250Black1000000000000000
    131
    		0.053"1.706"1.878"Durometer 90A (Hard)-40 to 250Black1000000000000000
    132
    		0.053"1.768"1.940"Durometer 90A (Hard)-40 to 250Black1000000000000000
    134
    		0.053"1.893"2.065"Durometer 90A (Hard)-40 to 250Black1000000000000000
    135
    		0.053"1.956"2.128"Durometer 90A (Hard)-40 to 250Black100000000000000
    136
    		0.053"2.018"2.190"Durometer 90A (Hard)-40 to 250Black50000000000000
    137
    		0.053"2.081"2.253"Durometer 90A (Hard)-40 to 250Black50000000000000
    141
    		0.053"2.331"2.503"Durometer 90A (Hard)-40 to 250Black500000000000000
    152
    		0.053"3.268"3.440"Durometer 90A (Hard)-40 to 250Black25000000000000
    154
    		0.053"3.768"3.940"Durometer 90A (Hard)-40 to 250Black10000000000000
    155
    		0.053"4.018"4.190"Durometer 90A (Hard)-40 to 250Black1000000000000
    158
    		0.053"4.768"4.940"Durometer 90A (Hard)-40 to 250Black10000000000000
     
    0.118" Wide
    202
    		0.05"0.265"0.501"Durometer 90A (Hard)-40 to 250Black100000000000000
    203
    		0.05"0.327"0.563"Durometer 90A (Hard)-40 to 250Black100000000000000
    204
    		0.05"0.390"0.626"Durometer 90A (Hard)-40 to 250Black100000000000000
    206
    		0.05"0.518"0.754"Durometer 90A (Hard)-40 to 250Black100000000000000
    207
    		0.05"0.580"0.816"Durometer 90A (Hard)-40 to 250Black10000000000000
    208
    		0.05"0.643"0.879"Durometer 90A (Hard)-40 to 250Black100000000000000
    210
    		0.05"0.766"1.002"Durometer 90A (Hard)-40 to 250Black100000000000000
    211
    		0.05"0.828"1.064"Durometer 90A (Hard)-40 to 250Black100000000000000
    212
    		0.05"0.891"1.127"Durometer 90A (Hard)-40 to 250Black100000000000000
    214
    		0.05"1.016"1.252"Durometer 90A (Hard)-40 to 250Black100000000000000
    216
    		0.05"1.141"1.377"Durometer 90A (Hard)-40 to 250Black100000000000000
    217
    		0.05"1.203"1.439"Durometer 90A (Hard)-40 to 250Black10000000000000
    218
    		0.05"1.266"1.502"Durometer 90A (Hard)-40 to 250Black1000000000000000
    220
    		0.05"1.397"1.633"Durometer 90A (Hard)-40 to 250Black50000000000000
    222
    		0.05"1.522"1.758"Durometer 90A (Hard)-40 to 250Black50000000000000
    223
    		0.05"1.647"1.833"Durometer 90A (Hard)-40 to 250Black50000000000000
    224
    		0.05"1.772"2.008"Durometer 90A (Hard)-40 to 250Black50000000000000
    225
    		0.05"1.897"2.133"Durometer 90A (Hard)-40 to 250Black50000000000000
    226
    		0.05"2.022"2.258"Durometer 90A (Hard)-40 to 250Black50000000000000
    227
    		0.05"2.147"2.383"Durometer 90A (Hard)-40 to 250Black50000000000000
    228
    		0.05"2.272"2.508"Durometer 90A (Hard)-40 to 250Black500000000000000
    229
    		0.05"2.397"2.633"Durometer 90A (Hard)-40 to 250Black500000000000000
    230
    		0.05"2.522"2.758"Durometer 90A (Hard)-40 to 250Black500000000000000
    231
    		0.05"2.631"2.867"Durometer 90A (Hard)-40 to 250Black500000000000000
    232
    		0.05"2.756"2.992"Durometer 90A (Hard)-40 to 250Black500000000000000
    233
    		0.05"2.881"3.117"Durometer 90A (Hard)-40 to 250Black25000000000000
    234
    		0.05"3.006"3.242"Durometer 90A (Hard)-40 to 250Black25000000000000
    235
    		0.05"3.131"3.367"Durometer 90A (Hard)-40 to 250Black25000000000000
    236
    		0.05"3.256"3.492"Durometer 90A (Hard)-40 to 250Black25000000000000
    237
    		0.05"3.381"3.617"Durometer 90A (Hard)-40 to 250Black2500000000000
    238
    		0.05"3.506"3.742"Durometer 90A (Hard)-40 to 250Black250000000000000
    239
    		0.05"3.631"3.867"Durometer 90A (Hard)-40 to 250Black250000000000000
    240
    		0.05"3.756"3.992"Durometer 90A (Hard)-40 to 250Black250000000000000
    241
    		0.05"3.881"4.117"Durometer 90A (Hard)-40 to 250Black250000000000000
    242
    		0.05"4.006"4.242"Durometer 90A (Hard)-40 to 250Black250000000000000
    243
    		0.05"4.131"4.367"Durometer 90A (Hard)-40 to 250Black250000000000000
    244
    		0.05"4.256"4.492"Durometer 90A (Hard)-40 to 250Black250000000000000
    245
    		0.05"4.381"4.617"Durometer 90A (Hard)-40 to 250Black250000000000000
    246
    		0.05"4.506"4.742"Durometer 90A (Hard)-40 to 250Black250000000000000
    247
    		0.05"4.631"4.867"Durometer 90A (Hard)-40 to 250Black25000000000000
    248
    		0.05"4.768"5.004"Durometer 90A (Hard)-40 to 250Black250000000000000
    249
    		0.05"4.893"5.129"Durometer 90A (Hard)-40 to 250Black250000000000000
    250
    		0.05"5.018"5.254"Durometer 90A (Hard)-40 to 250Black10000000000000
    252
    		0.05"5.268"5.504"Durometer 90A (Hard)-40 to 250Black10000000000000
    254
    		0.05"5.518"5.754"Durometer 90A (Hard)-40 to 250Black10000000000000
    255
    		0.05"5.643"5.879"Durometer 90A (Hard)-40 to 250Black10000000000000
    256
    		0.05"5.768"6.004"Durometer 90A (Hard)-40 to 250Black10000000000000
    257
    		0.05"5.893"6.129"Durometer 90A (Hard)-40 to 250Black1000000000000
    258
    		0.05"6.018"6.254"Durometer 90A (Hard)-40 to 250Black10000000000000
    259
    		0.05"6.268"6.504"Durometer 90A (Hard)-40 to 250Black10000000000000
    260
    		0.05"6.518"6.754"Durometer 90A (Hard)-40 to 250Black10000000000000
    261
    		0.05"6.768"7.004"Durometer 90A (Hard)-40 to 250Black10000000000000
    262
    		0.05"7.018"7.254"Durometer 90A (Hard)-40 to 250Black100000000000000
    265
    		0.05"7.768"8.004"Durometer 90A (Hard)-40 to 250Black100000000000000
     
    0.183" Wide
    322
    		0.076"1.263"1.629"Durometer 90A (Hard)-40 to 250Black50000000000000
    323
    		0.076"1.316"1.682"Durometer 90A (Hard)-40 to 250Black50000000000000
    325
    		0.076"1.513"1.879"Durometer 90A (Hard)-40 to 250Black50000000000000
    326
    		0.076"1.638"2.004"Durometer 90A (Hard)-40 to 250Black500000000000000
    329
    		0.076"2.013"2.379"Durometer 90A (Hard)-40 to 250Black500000000000000
    330
    		0.076"2.138"2.504"Durometer 90A (Hard)-40 to 250Black500000000000000
    333
    		0.076"2.518"2.884"Durometer 90A (Hard)-40 to 250Black500000000000000
    334
    		0.076"2.643"3.009"Durometer 90A (Hard)-40 to 250Black500000000000000
    337
    		0.076"3.018"3.384"Durometer 90A (Hard)-40 to 250Black250000000000000
    338
    		0.076"3.143"3.509"Durometer 90A (Hard)-40 to 250Black250000000000000
    339
    		0.076"3.273"3.639"Durometer 90A (Hard)-40 to 250Black250000000000000
    340
    		0.076"3.398"3.764"Durometer 90A (Hard)-40 to 250Black250000000000000
    341
    		0.076"3.523"3.889"Durometer 90A (Hard)-40 to 250Black25000000000000
    342
    		0.076"3.648"4.014"Durometer 90A (Hard)-40 to 250Black250000000000000
    343
    		0.076"3.773"4.139"Durometer 90A (Hard)-40 to 250Black250000000000000
    344
    		0.076"3.898"4.264"Durometer 90A (Hard)-40 to 250Black250000000000000
    345
    		0.076"4.028"4.394"Durometer 90A (Hard)-40 to 250Black250000000000000
    346
    		0.076"4.153"4.519"Durometer 90A (Hard)-40 to 250Black250000000000000
    349
    		0.076"4.528"4.894"Durometer 90A (Hard)-40 to 250Black10000000000000
    351
    		0.076"4.778"5.144"Durometer 90A (Hard)-40 to 250Black1000000000000
    358
    		0.076"5.653"6.019"Durometer 90A (Hard)-40 to 250Black100000000000000
     
    0.236" Wide
    426
    		0.117"4.676"5.148"Durometer 90A (Hard)-40 to 250Black100000000000000
    427
    		0.117"4.801"5.273"Durometer 90A (Hard)-40 to 250Black100000000000000
    429
    		0.117"5.051"5.523"Durometer 90A (Hard)-40 to 250Black100000000000000
    433
    		0.117"5.551"6.023"Durometer 90A (Hard)-40 to 250Black100000000000000
    437
    		0.117"6.051"6.523"Durometer 90A (Hard)-40 to 250Black100000000000000
    439
    		0.117"6.524"6.996"Durometer 90A (Hard)-40 to 250Black100000000000000
    443
    		0.117"7.524"7.996"Durometer 90A (Hard)-40 to 250Black100000000000000
    446
    		0.117"8.524"8.996"Durometer 90A (Hard)-40 to 250Black50000000000000
    451
    		0.117"11.024"11.496"Durometer 90A (Hard)-40 to 250Black50000000000000
    452
    		0.117"11.524"11.996"Durometer 90A (Hard)-40 to 250Black50000000000000
     

    Piston Seals for O-Ring Grooves
    3D CAD models available

    Image of Product. Front orientation. Piston Seals. Piston Seals for O-Ring Grooves.
    Image of Product. Profile. Front orientation. CrossSection view. Piston Seals. Piston Seals for O-Ring Grooves.
    Image of Attribute. Front orientation. Contains Annotated. Piston Seals for O-Ring Grooves.

    Profile

    Avoid common O-ring failure in dynamic applications—the square base of these seals prevents twisting, while backup rings protect against extrusion.
    Note: Maximum performance values cannot be achieved simultaneously; for example, speed is affected by pressure, temperature, and other operating conditions.
    For
    Groove
    For Bore
    Dia.
    Dia.
    Wd.
    O-Ring Dash
    No. Equiv.
    Max. Speed,
    ft/sec
    Max. Pressure,
    psi
    Temp. Range,
    ° F
    Hardness
    Color
    Each
    Buna-N with Nylon Backup Ring
    5/8"0.381"0.187"204
    		1.65,000-40 to 225Durometer 70A (Hard)Black000000000000
    3/4"0.506"0.187"206
    		1.65,000-40 to 225Durometer 70A (Hard)Black00000000000
    7/8"0.631"0.187"208
    		1.65,000-40 to 225Durometer 70A (Hard)Black00000000000
    1"0.757"0.187"210
    		1.65,000-40 to 225Durometer 70A (Hard)Black00000000000
    1 1/8"0.882"0.187"212
    		1.65,000-40 to 225Durometer 70A (Hard)Black00000000000
    1 1/4"1.007"0.187"214
    		1.65,000-40 to 225Durometer 70A (Hard)Black00000000000
    1 1/2"1.257"0.187"218
    		1.65,000-40 to 225Durometer 70A (Hard)Black00000000000
    1 3/4"1.507"0.187"222
    		1.65,000-40 to 225Durometer 70A (Hard)Black00000000000
    2"1.628"0.282"326
    		1.65,000-40 to 225Durometer 70A (Hard)Black000000000000
    2 1/4"1.878"0.282"328
    		1.65,000-40 to 225Durometer 70A (Hard)Black000000000000
    2 1/2"2.128"0.282"330
    		1.65,000-40 to 225Durometer 70A (Hard)Black000000000000
    3"2.628"0.282"334
    		1.65,000-40 to 225Durometer 70A (Hard)Black000000000000
    3 1/2"3.129"0.282"338
    		1.65,000-40 to 225Durometer 70A (Hard)Black000000000000
    4"3.629"0.282"342
    		1.65,000-40 to 225Durometer 70A (Hard)Black000000000000
     

    Rod Seals for O-Ring Grooves
    3D CAD models available

    Image of Product. Profile. Front orientation. CrossSection view. Rod Seals. Rod Seals for O-Ring Grooves.
    Image of Attribute. Front orientation. Contains Annotated. Rod Seals for O-Ring Grooves.

    Profile

    Avoid common O-ring failure in dynamic applications—the square base of these seals prevents twisting, while backup rings protect against extrusion.
    Note: Maximum performance values cannot be achieved simultaneously; for example, speed is affected by pressure, temperature, and other operating conditions.
    For
    Groove
    For Rod
    Dia.
    Dia.
    Wd.
    O-Ring Dash
    No. Equiv.
    Max. Speed,
    ft/sec
    Max. Pressure,
    psi
    Temp. Range,
    ° F
    Hardness
    Color
    Backup
    Ring
    Color
    Each
    Buna-N with Nylon Backup Ring
    1/2"0.742"0.187"206
    		1.65,000-40 to 225Durometer 75A (Hard)BlackGray000000000000
    5/8"0.867"0.187"208
    		1.65,000-40 to 225Durometer 70A (Hard)BlackGray00000000000
    3/4"0.991"0.187"210
    		1.65,000-40 to 225Durometer 70A (Hard)BlackGray00000000000
    1 1/8"1.366"0.187"216
    		1.65,000-40 to 225Durometer 70A (Hard)BlackGray00000000000
    1 1/2"1.870"0.282"325
    		1.65,000-40 to 225Durometer 70A (Hard)BlackGray00000000000
    2"2.370"0.282"329
    		1.65,000-40 to 225Durometer 70A (Hard)BlackGray000000000000
    2 1/4"2.612"0.282"331
    		1.65,000-40 to 225Durometer 70A (Hard)BlackGray000000000000
    2 1/2"2.870"0.282"333
    		1.65,000-40 to 225Durometer 70A (Hard)BlackGray000000000000
    3"3.369"0.282"337
    		1.65,000-40 to 225Durometer 70A (Hard)BlackGray000000000000
     
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