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    168 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.

    High-Pressure Ultra-Chemical-Resistant PTFE Backup Rings

    Image of ProductInUse. O-Ring Deforms Without a Backup Ring. Front orientation. CrossSection view. Contains Annotated. Backup Rings. Ultra Chemical Resistant, PTFE.
    Image of ProductInUse. O-Ring Sealing Properly with Backup Ring. Front orientation. CrossSection view. Contains Annotated. Backup Rings. Ultra Chemical Resistant, PTFE.

    O-Ring Deforms Without a Backup Ring

    O-Ring Sealing Properly with

    Backup Ring

    Image of Product. Front orientation. Backup Rings. Ultra Chemical Resistant, PTFE.
    Image of Attribute. Front orientation. CrossSection view. Contains Annotated. Ultra Chemical Resistant, PTFE.
    Protect O-rings in equipment operating at pressures up to 4,300 psi. These backup rings support O-rings to extend their life and prevent them from deforming under pressure, which can cause pressure loss. Made of PTFE, they’re rigid enough to hold their shape under load, yet slippery enough to reduce friction in moving parts. They also resist a wide range of chemicals. Often used in pipeline valves and chemical processing equipment, they have a split ring design to simplify installation. 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
    005
    0.049"0.124"0.230"Durometer 55D (Hard)-300 to 500White259560K2110000000000
    006
    0.049"0.140"0.246"Durometer 55D (Hard)-300 to 500White259560K21200000000
    007
    0.049"0.171"0.277"Durometer 55D (Hard)-300 to 500White259560K21300000000
    008
    0.049"0.202"0.308"Durometer 55D (Hard)-300 to 500White259560K21400000000
    009
    0.049"0.234"0.340"Durometer 55D (Hard)-300 to 500White259560K21500000000
    010
    0.049"0.265"0.371"Durometer 55D (Hard)-300 to 500White259560K21600000000
    011
    0.049"0.327"0.433"Durometer 55D (Hard)-300 to 500White259560K21700000000
    012
    0.049"0.390"0.496"Durometer 55D (Hard)-300 to 500White259560K21800000000
    013
    0.049"0.455"0.561"Durometer 55D (Hard)-300 to 500White259560K21900000000
    014
    0.049"0.518"0.624"Durometer 55D (Hard)-300 to 500White259560K22100000000
    015
    0.049"0.580"0.686"Durometer 55D (Hard)-300 to 500White259560K22200000000
    016
    0.049"0.643"0.749"Durometer 55D (Hard)-300 to 500White259560K22300000000
    017
    0.049"0.705"0.811"Durometer 55D (Hard)-300 to 500White259560K22400000000
    018
    0.049"0.768"0.874"Durometer 55D (Hard)-300 to 500White259560K22500000000
    019
    0.049"0.830"0.936"Durometer 55D (Hard)-300 to 500White259560K2260000000000
    020
    0.049"0.898"1.004"Durometer 55D (Hard)-300 to 500White259560K2270000000000
    021
    0.049"0.960"1.066"Durometer 55D (Hard)-300 to 500White109560K22800000000
    022
    0.049"1.023"1.129"Durometer 55D (Hard)-300 to 500White109560K22900000000
    023
    0.049"1.085"1.191"Durometer 55D (Hard)-300 to 500White109560K23100000000
    024
    0.049"1.148"1.254"Durometer 55D (Hard)-300 to 500White109560K232000000000
    025
    0.049"1.210"1.316"Durometer 55D (Hard)-300 to 500White109560K2330000000000
    026
    0.049"1.273"1.379"Durometer 55D (Hard)-300 to 500White109560K2340000000000
    027
    0.049"1.335"1.441"Durometer 55D (Hard)-300 to 500White109560K2350000000000
    028
    0.049"1.398"1.504"Durometer 55D (Hard)-300 to 500White109560K2360000000000
    029
    0.049"1.523"1.629"Durometer 55D (Hard)-300 to 500White109560K2370000000000
    030
    0.049"1.648"1.754"Durometer 55D (Hard)-300 to 500White59560K23800000000
    031
    0.049"1.773"1.879"Durometer 55D (Hard)-300 to 500White59560K23900000000
    032
    0.049"1.898"2.004"Durometer 55D (Hard)-300 to 500White59560K24100000000
    033
    0.049"2.023"2.129"Durometer 55D (Hard)-300 to 500White59560K24200000000
    034
    0.049"2.148"2.254"Durometer 55D (Hard)-300 to 500White19560K24300000000
    035
    0.049"2.273"2.379"Durometer 55D (Hard)-300 to 500White19560K24400000000
    036
    0.049"2.398"2.504"Durometer 55D (Hard)-300 to 500White19560K24500000000
    037
    0.049"2.523"2.629"Durometer 55D (Hard)-300 to 500White19560K24600000000
    038
    0.049"2.648"2.754"Durometer 55D (Hard)-300 to 500White19560K24700000000
    041
    0.049"3.023"3.129"Durometer 55D (Hard)-300 to 500White19560K24800000000
    042
    0.049"3.273"3.379"Durometer 55D (Hard)-300 to 500White19560K24900000000
     
    0.086" Wide
    109
    0.049"0.328"0.500"Durometer 55D (Hard)-300 to 500White259560K2510000000000
    110
    0.049"0.390"0.562"Durometer 55D (Hard)-300 to 500White259560K25200000000
    111
    0.049"0.452"0.624"Durometer 55D (Hard)-300 to 500White259560K25300000000
    112
    0.049"0.515"0.687"Durometer 55D (Hard)-300 to 500White259560K25400000000
    113
    0.049"0.577"0.749"Durometer 55D (Hard)-300 to 500White259560K25500000000
    114
    0.049"0.640"0.812"Durometer 55D (Hard)-300 to 500White259560K25600000000
    115
    0.049"0.702"0.874"Durometer 55D (Hard)-300 to 500White259560K25700000000
    116
    0.049"0.765"0.937"Durometer 55D (Hard)-300 to 500White259560K25800000000
    117
    0.049"0.832"1.004"Durometer 55D (Hard)-300 to 500White259560K4900000000
    118
    0.049"0.895"1.067"Durometer 55D (Hard)-300 to 500White259560K26100000000
    119
    0.049"0.957"1.129"Durometer 55D (Hard)-300 to 500White259560K21000000000
    120
    0.049"1.020"1.192"Durometer 55D (Hard)-300 to 500White259560K22000000000
    121
    0.049"1.082"1.254"Durometer 55D (Hard)-300 to 500White259560K23000000000
    122
    0.049"1.145"1.317"Durometer 55D (Hard)-300 to 500White109560K2650000000000
    123
    0.049"1.207"1.379"Durometer 55D (Hard)-300 to 500White109560K266000000000
    124
    0.049"1.270"1.442"Durometer 55D (Hard)-300 to 500White109560K267000000000
    125
    0.049"1.332"1.504"Durometer 55D (Hard)-300 to 500White109560K268000000000
    126
    0.049"1.397"1.569"Durometer 55D (Hard)-300 to 500White109560K2690000000000
    127
    0.049"1.459"1.631"Durometer 55D (Hard)-300 to 500White59560K27100000000
    128
    0.049"1.522"1.694"Durometer 55D (Hard)-300 to 500White59560K27200000000
    129
    0.049"1.584"1.756"Durometer 55D (Hard)-300 to 500White59560K27300000000
    130
    0.049"1.647"1.819"Durometer 55D (Hard)-300 to 500White59560K27400000000
    131
    0.049"1.709"1.881"Durometer 55D (Hard)-300 to 500White59560K27500000000
    132
    0.049"1.772"1.944"Durometer 55D (Hard)-300 to 500White59560K27600000000
    133
    0.049"1.834"2.006"Durometer 55D (Hard)-300 to 500White59560K27700000000
    134
    0.049"1.897"2.069"Durometer 55D (Hard)-300 to 500White59560K278000000000
    135
    0.049"1.959"2.131"Durometer 55D (Hard)-300 to 500White59560K279000000000
    136
    0.049"2.022"2.194"Durometer 55D (Hard)-300 to 500White19560K28100000000
    137
    0.049"2.084"2.256"Durometer 55D (Hard)-300 to 500White19560K28200000000
    138
    0.049"2.147"2.319"Durometer 55D (Hard)-300 to 500White19560K28300000000
    139
    0.049"2.209"2.381"Durometer 55D (Hard)-300 to 500White19560K28400000000
    140
    0.049"2.258"2.430"Durometer 55D (Hard)-300 to 500White19560K28500000000
    141
    0.049"2.320"2.492"Durometer 55D (Hard)-300 to 500White19560K28600000000
    142
    0.049"2.383"2.555"Durometer 55D (Hard)-300 to 500White19560K28700000000
    143
    0.049"2.445"2.617"Durometer 55D (Hard)-300 to 500White19560K28800000000
    144
    0.049"2.508"2.680"Durometer 55D (Hard)-300 to 500White19560K28900000000
    145
    0.049"2.570"2.742"Durometer 55D (Hard)-300 to 500White19560K29100000000
    146
    0.049"2.633"2.805"Durometer 55D (Hard)-300 to 500White19560K29200000000
    147
    0.049"2.685"2.857"Durometer 55D (Hard)-300 to 500White19560K29300000000
    148
    0.049"2.758"2.930"Durometer 55D (Hard)-300 to 500White19560K29400000000
    150
    0.049"2.883"3.055"Durometer 55D (Hard)-300 to 500White19560K29500000000
    151
    0.049"3.008"3.180"Durometer 55D (Hard)-300 to 500White19560K29600000000
    152
    0.049"3.258"3.430"Durometer 55D (Hard)-300 to 500White19560K29700000000
    158
    0.049"4.758"4.930"Durometer 55D (Hard)-300 to 500White19560K2980000000000
     
    0.119" Wide
    208
    0.049"0.613"0.851"Durometer 55D (Hard)-300 to 500White109560K29900000000
    209
    0.049"0.675"0.913"Durometer 55D (Hard)-300 to 500White109560K31100000000
    210
    0.049"0.766"1.004"Durometer 55D (Hard)-300 to 500White109560K31200000000
    211
    0.049"0.828"1.066"Durometer 55D (Hard)-300 to 500White109560K31300000000
    212
    0.049"0.891"1.129"Durometer 55D (Hard)-300 to 500White109560K31400000000
    213
    0.049"0.953"1.191"Durometer 55D (Hard)-300 to 500White109560K31500000000
    214
    0.049"1.016"1.254"Durometer 55D (Hard)-300 to 500White109560K31600000000
    215
    0.049"1.078"1.316"Durometer 55D (Hard)-300 to 500White109560K31700000000
    216
    0.049"1.141"1.379"Durometer 55D (Hard)-300 to 500White109560K31800000000
    217
    0.049"1.203"1.441"Durometer 55D (Hard)-300 to 500White109560K31900000000
    218
    0.049"1.266"1.504"Durometer 55D (Hard)-300 to 500White109560K32100000000
    219
    0.049"1.334"1.572"Durometer 55D (Hard)-300 to 500White109560K32200000000
    220
    0.049"1.397"1.635"Durometer 55D (Hard)-300 to 500White109560K32300000000
    221
    0.049"1.459"1.697"Durometer 55D (Hard)-300 to 500White109560K32400000000
    222
    0.049"1.522"1.760"Durometer 55D (Hard)-300 to 500White109560K325000000000
    223
    0.049"1.647"1.885"Durometer 55D (Hard)-300 to 500White109560K326000000000
    224
    0.049"1.772"2.010"Durometer 55D (Hard)-300 to 500White109560K327000000000
    225
    0.049"1.897"2.135"Durometer 55D (Hard)-300 to 500White59560K3280000000000
    226
    0.049"2.022"2.260"Durometer 55D (Hard)-300 to 500White59560K32900000000
    227
    0.049"2.147"2.385"Durometer 55D (Hard)-300 to 500White59560K33100000000
    228
    0.049"2.272"2.510"Durometer 55D (Hard)-300 to 500White59560K33200000000
    229
    0.049"2.397"2.635"Durometer 55D (Hard)-300 to 500White59560K33300000000
    230
    0.049"2.522"2.760"Durometer 55D (Hard)-300 to 500White59560K33400000000
    231
    0.049"2.631"2.869"Durometer 55D (Hard)-300 to 500White59560K33500000000
    232
    0.049"2.756"2.994"Durometer 55D (Hard)-300 to 500White19560K33600000000
    233
    0.049"2.881"3.119"Durometer 55D (Hard)-300 to 500White19560K33700000000
    234
    0.049"3.006"3.244"Durometer 55D (Hard)-300 to 500White19560K33800000000
    235
    0.049"3.131"3.369"Durometer 55D (Hard)-300 to 500White19560K33900000000
    236
    0.049"3.256"3.494"Durometer 55D (Hard)-300 to 500White19560K34100000000
    237
    0.049"3.381"3.619"Durometer 55D (Hard)-300 to 500White19560K34200000000
    238
    0.049"3.506"3.744"Durometer 55D (Hard)-300 to 500White19560K34300000000
    239
    0.049"3.631"3.869"Durometer 55D (Hard)-300 to 500White19560K34400000000
    240
    0.049"3.756"3.994"Durometer 55D (Hard)-300 to 500White19560K34500000000
    241
    0.049"3.881"4.119"Durometer 55D (Hard)-300 to 500White19560K34600000000
    242
    0.049"4.006"4.244"Durometer 55D (Hard)-300 to 500White19560K34700000000
    243
    0.049"4.131"4.369"Durometer 55D (Hard)-300 to 500White19560K34800000000
    244
    0.049"4.256"4.494"Durometer 55D (Hard)-300 to 500White19560K34900000000
    245
    0.049"4.381"4.619"Durometer 55D (Hard)-300 to 500White19560K35100000000
    246
    0.049"4.506"4.744"Durometer 55D (Hard)-300 to 500White19560K35200000000
    247
    0.049"4.631"4.869"Durometer 55D (Hard)-300 to 500White19560K35300000000
    248
    0.049"4.756"4.994"Durometer 55D (Hard)-300 to 500White19560K35400000000
    249
    0.049"4.881"5.119"Durometer 55D (Hard)-300 to 500White19560K35500000000
    250
    0.049"5.006"5.244"Durometer 55D (Hard)-300 to 500White19560K35600000000
    252
    0.049"5.256"5.494"Durometer 55D (Hard)-300 to 500White19560K357000000000
    254
    0.049"5.506"5.744"Durometer 55D (Hard)-300 to 500White19560K358000000000
    255
    0.049"5.631"5.869"Durometer 55D (Hard)-300 to 500White19560K3590000000000
    256
    0.049"5.756"5.994"Durometer 55D (Hard)-300 to 500White19560K3610000000000
    257
    0.049"5.881"6.119"Durometer 55D (Hard)-300 to 500White19560K3620000000000
    258
    0.049"6.006"6.244"Durometer 55D (Hard)-300 to 500White19560K363000000000
    259
    0.049"6.256"6.494"Durometer 55D (Hard)-300 to 500White19560K3640000000000
    260
    0.049"6.506"6.744"Durometer 55D (Hard)-300 to 500White19560K3650000000000
    261
    0.049"6.758"6.996"Durometer 55D (Hard)-300 to 500White19560K3660000000000
    263
    0.049"7.258"7.496"Durometer 55D (Hard)-300 to 500White19560K3670000000000
    264
    0.049"7.508"7.746"Durometer 55D (Hard)-300 to 500White19560K3680000000000
    265
    0.049"7.758"7.996"Durometer 55D (Hard)-300 to 500White19560K3690000000000
     
    0.183" Wide
    325
    0.07"1.513"1.879"Durometer 55D (Hard)-300 to 500White59560K37100000000
    326
    0.07"1.638"2.004"Durometer 55D (Hard)-300 to 500White59560K37200000000
    327
    0.07"1.763"2.129"Durometer 55D (Hard)-300 to 500White59560K37300000000
    328
    0.07"1.888"2.254"Durometer 55D (Hard)-300 to 500White59560K37400000000
    329
    0.07"2.013"2.379"Durometer 55D (Hard)-300 to 500White59560K37500000000
    330
    0.07"2.138"2.504"Durometer 55D (Hard)-300 to 500White59560K37600000000
    331
    0.07"2.268"2.634"Durometer 55D (Hard)-300 to 500White59560K37700000000
    332
    0.07"2.393"2.759"Durometer 55D (Hard)-300 to 500White59560K378000000000
    333
    0.07"2.518"2.884"Durometer 55D (Hard)-300 to 500White59560K379000000000
    334
    0.07"2.643"3.009"Durometer 55D (Hard)-300 to 500White19560K38100000000
    335
    0.07"2.768"3.134"Durometer 55D (Hard)-300 to 500White19560K38200000000
    336
    0.07"2.893"3.259"Durometer 55D (Hard)-300 to 500White19560K38300000000
    337
    0.07"3.018"3.384"Durometer 55D (Hard)-300 to 500White19560K38400000000
    338
    0.07"3.143"3.509"Durometer 55D (Hard)-300 to 500White19560K38500000000
    339
    0.07"3.273"3.639"Durometer 55D (Hard)-300 to 500White19560K38600000000
    340
    0.07"3.398"3.764"Durometer 55D (Hard)-300 to 500White19560K38700000000
    341
    0.07"3.523"3.889"Durometer 55D (Hard)-300 to 500White19560K38800000000
    342
    0.07"3.648"4.014"Durometer 55D (Hard)-300 to 500White19560K38900000000
    343
    0.07"3.773"4.139"Durometer 55D (Hard)-300 to 500White19560K39100000000
    344
    0.07"3.898"4.264"Durometer 55D (Hard)-300 to 500White19560K39200000000
    345
    0.07"4.028"4.394"Durometer 55D (Hard)-300 to 500White19560K39300000000
    346
    0.07"4.153"4.519"Durometer 55D (Hard)-300 to 500White19560K39400000000
    347
    0.07"4.278"4.644"Durometer 55D (Hard)-300 to 500White19560K39500000000
    348
    0.07"4.403"4.769"Durometer 55D (Hard)-300 to 500White19560K39600000000
    349
    0.07"4.528"4.894"Durometer 55D (Hard)-300 to 500White19560K39700000000
    358
    0.07"5.653"6.019"Durometer 55D (Hard)-300 to 500White19560K3980000000000
     
    0.236" Wide
    426
    0.105"4.676"5.148"Durometer 55D (Hard)-300 to 500White19560K3990000000000
    429
    0.105"5.051"5.523"Durometer 55D (Hard)-300 to 500White19560K4120000000000
    433
    0.105"5.551"6.023"Durometer 55D (Hard)-300 to 500White19560K4130000000000
    439
    0.105"6.524"6.996"Durometer 55D (Hard)-300 to 500White19560K4140000000000
    443
    0.105"7.524"7.996"Durometer 55D (Hard)-300 to 500White19560K4150000000000
    446
    0.105"8.524"8.996"Durometer 55D (Hard)-300 to 500White19560K4160000000000
    452
    0.105"11.524"11.996"Durometer 55D (Hard)-300 to 500White19560K4170000000000
     
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