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    10 Products

    Insulating Cup Washers

    Image of Product. Front orientation. Insulating Washers. Insulating Cup Washers.
    Cover screw heads or nuts to block electrical current and prevent short circuits. These washers isolate fasteners from sensitive surface-mounted components, such as capacitators and transistors on printed circuit boards. They also extend the life of your assembly by preventing galvanic corrosion, which is when two different metals rust more quickly due to contact with each other.
    Nylon—Our most versatile insulating washers, these block unwanted current in everything from switches and circuit breakers to control panels and electric motors.
    Very-High-Temperature Ceramic—Our most heat-resistant washers and the best electrical insulators. These won't melt or become brittle at blistering temperatures up to 1,700° F, making them perfect for ovens, kilns, and furnaces. Ceramic may crack or dent if subjected to hard bumps, however, so these washers are not recommended for high-vibration applications.
    Temp.
    Range, ° F
    For Screw
    Size
    ID
    OD
    Cup
    ID
    Inside
    Dp.
    Thk.
    Overall
    Ht.
    Min.
    Max.
    Color
    Pkg.
    Qty.
    Pkg.
    Nylon
    No. 4
    0.115"0.305"0.245"0.117"0.040"0.157"-40180Off-White10000000000000000
    No. 6
    0.140"0.360"0.300"0.142"0.040"0.182"-40180Off-White1000000000000000
    No. 8
    0.171"0.414"0.354"0.166"0.040"0.206"-40180Off-White1000000000000000
    No. 10
    0.194"0.470"0.410"0.190"0.040"0.230"-40180Off-White1000000000000000
    1/4"
    0.257"0.595"0.535"0.247"0.042"0.289"-40180Off-White1000000000000000
     
    Very-High-Temperature Ceramic
    No. 4
    0.130"0.440"0.250"0.125"0.100"0.225"Not Rated1,700Off-White10000000000000
    No. 6
    0.160"0.500"0.312"0.150"0.100"0.250"Not Rated1,700Off-White10000000000000
    No. 8
    0.180"0.560"0.375"0.170"0.100"0.270"Not Rated1,700Off-White10000000000000
    No. 10
    0.200"0.625"0.437"0.190"0.100"0.290"Not Rated1,700Off-White10000000000000
    1/4"
    0.260"0.750"0.531"0.250"0.100"0.350"Not Rated1,700Off-White10000000000000
     
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