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    25 Products

    Insulating Sleeve Washers

    Cover screw threads to stop electrical current in its tracks and prevent short circuits. These washers create a barrier between the screw threads and the mating surface when mounted in through holes. This barrier also extends the life of your assembly by preventing galvanic corrosion, which is when two different metals rust more quickly due to contact with each other.
    Flat Edge
    Image of Product. Front orientation. Insulating Washers. Insulating Sleeve Washers, Flat Edge.
    The flat edge distributes weight evenly to take pressure off screw heads.
    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.
    Sleeve
    Temp.
    Range
    For Screw
    Size
    Ht.
    OD
    ID
    OD
    Thk.
    Overall
    Ht.
    Min.
    Max.,
    ° F
    Color
    Pkg.
    Qty.
    Pkg.
    Very-High-Temperature Ceramic
    No. 6
    0.062"0.281"0.150"0.500"0.125"0.187"Not Rated1,700Off-White5000000000000000
    No. 6
    0.250"0.281"0.150"0.500"0.187"0.437"Not Rated1,700Off-White500000000000000
    No. 8
    0.062"0.406"0.175"0.625"0.125"0.187"Not Rated1,700Off-White500000000000000
    No. 8
    0.250"0.406"0.175"0.625"0.218"0.468"Not Rated1,700Off-White500000000000000
    No. 10
    0.062"0.468"0.200"0.750"0.156"0.218"Not Rated1,700Off-White500000000000000
    No. 10
    0.250"0.468"0.200"0.750"0.218"0.468"Not Rated1,700Off-White500000000000000
    1/4"
    0.062"0.593"0.265"0.875"0.188"0.250"Not Rated1,700Off-White500000000000000
    1/4"
    0.250"0.593"0.265"0.875"0.250"0.500"Not Rated1,700Off-White500000000000000
    M2
    2.500 mm3.000 mm2.100 mm4.200 mm1.500 mm4.000 mmNot Rated1,700Off-White10000000000000
    M3
    1.500 mm4.000 mm3.100 mm6.200 mm1.500 mm3.000 mmNot Rated1,700Off-White10000000000000
    M3
    3.500 mm4.000 mm3.100 mm6.200 mm1.500 mm5.000 mmNot Rated1,700Off-White10000000000000
    M3
    7.500 mm4.000 mm3.100 mm6.200 mm1.500 mm9.000 mmNot Rated1,700Off-White10000000000000
    M4
    3.000 mm6.000 mm4.100 mm8.400 mm1.500 mm4.500 mmNot Rated1,700Off-White10000000000000
    M4
    5.000 mm6.000 mm4.100 mm8.400 mm1.500 mm6.500 mmNot Rated1,700Off-White10000000000000
    M5
    3.000 mm7.000 mm5.100 mm10.200 mm2.000 mm5.000 mmNot Rated1,700Off-White10000000000000
    M5
    5.000 mm7.000 mm5.100 mm10.200 mm2.000 mm7.000 mmNot Rated1,700Off-White10000000000000
    M6
    4.000 mm8.000 mm6.100 mm12.200 mm2.000 mm6.000 mmNot Rated1,700Off-White10000000000000
    M6
    10.000 mm8.000 mm6.100 mm12.200 mm2.000 mm12.000 mmNot Rated1,700Off-White10000000000000
    M8
    4.000 mm10.000 mm8.100 mm14.200 mm2.500 mm6.500 mmNot Rated1,700Off-White10000000000000
    M8
    8.000 mm10.000 mm8.100 mm14.200 mm2.500 mm10.500 mmNot Rated1,700Off-White10000000000000
     

    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.
    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
    For Screw
    Size
    ID
    OD
    Cup
    ID
    Inside
    Dp.
    Thk.
    Overall
    Ht.
    Min.
    Max.,
    ° F
    Color
    Pkg.
    Qty.
    Pkg.
    Very-High-Temperature Ceramic
    No. 4
    0.130"0.440"0.250"0.125"0.100"0.225"Not Rated1,700Off-White100000000000000
    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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