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    127 Products

    High-Pressure Bonded Sealing Washers

    Tested to hold up to high pressures, these washers create the strongest seal of all to lock in air and fluid and keep equipment running efficiently. They are often used on flanged connections to prevent leaks in pumps, hydraulic systems, compressors, and other pressurized lines. The flexible rubber or plastic layer compresses to fills gaps, while the metal backing stops the washer from squeezing through the hole.
    For Screw Heads
    Image of ProductInUse. Front orientation. CrossSection view. Sealing Washers. High-Pressure Bonded Sealing Washers, For Screw Heads.
    Image of Product. Front orientation. Sealing Washers. High-Pressure Bonded Sealing Washers, For Screw Heads.
    Fit under screw heads to stop leaks. These washers seal best on screws that aren't threaded all the way up to the head. Reuse them a handful of times, as long as the material isn't damaged.
    Oil-Resistant Zinc-Plated Steel and Buna-N—These washers won't swell or soften when they touch oil, grease, and fuel. However, they will degrade if exposed to synthetic lubricants. They are also are more susceptible to rusting than 18-8 and 316 stainless steel.
    Max.
    Pressure, psi, psi
    Temp.
    Range, ° F
    For Screw
    Size
    ID
    OD
    Thk.
    For
    Fluids
    For
    Gases
    Min.
    Max.
    Color
    Pkg.
    Qty.
    Pkg.
    Oil-Resistant Zinc-Plated Steel and Buna-N
    No. 6
    0.13"0.385"0.036" to 0.044"10,800200-40225Black1093783A007000000
    No. 8
    0.156"0.385"0.036" to 0.044"8,000200-40225Black193783A0090000
    No. 10
    0.18"0.443"0.045" to 0.055"6,200200-40225Black193783A0110000
    1/4"
    0.24"0.505"0.045" to 0.055"5,000200-40225Black1093783A02900000
    5/16"
    0.301"0.603"0.045" to 0.055"3,600200-40225Black1093783A03000000
    3/8"
    0.364"0.666"0.045" to 0.055"3,400200-40225Black1093783A03100000
    7/16"
    0.427"0.76"0.045" to 0.055"3,600200-40225Black593783A03200000
    1/2"
    0.49"0.88"0.045" to 0.055"4,200200-40225Black1093783A03300000
    9/16"
    0.552"1.067"0.045" to 0.055"6,600200-30225Black593783A03400000
    5/8"
    0.615"1.193"0.045" to 0.055"7,500200-40225Black593783A03500000
    3/4"
    0.74"1.322"0.059" to 0.069"5,700200-40225Black593783A03600000
    1"
    0.988"1.76"0.059" to 0.069"7,000200-40225Black193783A0510000
     
    For Nuts
    Image of ProductInUse. Front orientation. CrossSection view. Sealing Washers. High-Pressure Bonded Sealing Washers, For Nuts.
    Image of Product. Front orientation. Sealing Washers. High-Pressure Bonded Sealing Washers, For Nuts.
    Commonly used under nuts, these washers wedge into threads to prevent liquids or gases from trickling along the length of the screw. Reuse them a handful of times, as long as the material isn't damaged.
    Oil-Resistant Zinc-Plated Steel and Buna-N—These washers won't swell or soften when they touch oil, grease, and fuel. However, they will degrade if exposed to synthetic lubricants. They are also are more susceptible to rusting than 18-8 and 316 stainless steel.
    Max.
    Pressure, psi
    Temp.
    Range, ° F
    For Screw
    Size
    ID
    OD
    Thk.
    For Fluids,
    psi
    For
    Gases
    Min.
    Max.
    Color
    Pkg.
    Qty.
    Pkg.
    Oil-Resistant Zinc-Plated Steel and Buna-N
    No. 6
    0.141"0.406"0.045" to 0.055"2,000Not Rated-30220Black593781A008000000
    No. 8
    0.167"0.406"0.045" to 0.055"2,000Not Rated-30220Black593781A01000000
    No. 10
    0.194"0.469"0.045" to 0.055"2,000Not Rated-30220Black593781A01100000
    1/4"
    0.255"0.562"0.045" to 0.055"5,000Not Rated-30220Black593781A02900000
    5/16"
    0.319"0.687"0.059" to 0.069"5,000Not Rated-30220Black593781A03700000
    3/8"
    0.383"0.750"0.059" to 0.069"5,000Not Rated-30220Black593781A03800000
    7/16"
    0.447"0.906"0.073" to 0.083"5,000Not Rated-30220Black593781A03200000
    1/2"
    0.510"1.000"0.073" to 0.083"5,000Not Rated-30220Black593781A03300000
    5/8"
    0.638"1.187"0.089" to 0.099"5,000Not Rated-30220Black593781A03500000
    3/4"
    0.765"1.375"0.104" to 0.114"5,000Not Rated-30220Black193781A0390000
    1"
    1.020"1.750"0.115" to 0.125"5,000Not Rated-30220Black193781A05100000
     

    Sealing Washers

    Prevent leaks while distributing weight evenly under nuts and screws. These washers compress as you tighten to keep air and fluid in, and dust and contaminants out. Use them anywhere you need a tight seal, such as protecting electronics from moisture or keeping lubricants contained in machinery.
    Rubber
    Image of Product. Front orientation. Sealing Washers. Rubber.
    Resist leaks better than metal sealing washers, but are more susceptible to wear and tear. Reuse these washers a handful of times, as long as the material isn't damaged.
    Neoprene—If you're not sure which material best suits your needs, these versatile washers are a great solution. They offer a good balance of strength and flexibility to hold a tight seal, even in wet and outdoor conditions. These washers also withstand salt water and mild chemicals, such as detergents. However, they don't resist oil, grease, or fuel as well as Buna-N washers.
    Oil-Resistant Buna-N—With the best oil resistance of all our rubber washers, these won't swell or soften when they touch oil, grease, or fuel. However, they will break down if exposed to synthetic lubricants.
    Weather-Resistant EPDM—The best choice for outdoor use, these washers withstand long-term exposure to sunlight, rain, and ozone. However, they can't handle oil, grease, or fuel like Buna-N washers can.
    Temp.
    Range, ° F
    For Screw
    Size
    ID
    OD
    Thk.
    Min.
    Max.
    Color
    Food Industry Std.
    Pkg.
    Qty.
    Pkg.
    Neoprene
    No. 2
    0.093"0.188"0.019" to 0.043"-20180Black10090133A101000000
    No. 4
    0.120"0.312"0.019" to 0.043"-20180Black10090133A10200000
    No. 5
    0.141"0.281"0.019" to 0.043"-20180Black10090133A10300000
    No. 6
    0.120"0.250"0.047" to 0.077"-20180Black10090133A00500000
    No. 6
    0.120"0.250"0.062"-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A11000000
    No. 6
    0.120"0.375"0.046" to 0.078"-20180Black5090133A5100000
    No. 6
    0.120"0.375"0.062"-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A12000000
    No. 8
    0.150"0.312"0.047" to 0.077"-20180Black10090133A00900000
    No. 8
    0.150"0.312"0.062"-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A13000000
    No. 8
    0.150"0.438"0.046" to 0.078"-20180Black5090133A5200000
    No. 8
    0.150"0.438"0.062"-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A14000000
    No. 10
    0.170"0.375"0.062"-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A15000000
    No. 10
    0.170"0.375"0.078" to 0.108"-20180Black10090133A01300000
    No. 10
    0.170"0.500"0.062"-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A16000000
    No. 10
    0.170"0.500"0.078" to 0.108"-20180Black10090133A01700000
    No. 12
    0.195"0.438"0.062"-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A17000000
    No. 12
    0.195"0.438"0.078" to 0.108"-20180Black10090133A02100000
    No. 12
    0.195"0.562"0.062"-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A18000000
    No. 12
    0.195"0.562"0.078" to 0.108"-20180Black10090133A02500000
    No. 14
    0.230"0.500"0.046" to 0.078"-20180Black5090133A5300000
    No. 14
    0.230"0.500"0.062"-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A19000000
    No. 14
    0.230"0.625"0.046" to 0.078"-20180Black5090133A5400000
    No. 14
    0.230"0.625"0.062"-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A21000000
    1/4"
    0.230"0.500"0.078" to 0.108"-20180Black10090133A02900000
    1/4"
    0.230"0.625"0.078" to 0.108"-20180Black10090133A03200000
    5/16"
    0.290"0.562"0.062"-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A22000000
    5/16"
    0.290"0.562"0.078" to 0.108"-20180Black10090133A03600000
    5/16"
    0.290"0.688"0.062"-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A23000000
    5/16"
    0.290"0.688"0.078" to 0.108"-20180Black10090133A04000000
    3/8"
    0.355"0.625"0.062"-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A24000000
    3/8"
    0.355"0.625"0.078" to 0.108"-20180Black10090133A04400000
    3/8"
    0.355"0.812"0.062"-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A25000000
    3/8"
    0.355"0.812"0.078" to 0.108"-20180Black5090133A04800000
    3/8"
    0.355"0.812"0.110" to 0.140"-20180Black5090133A4200000
    7/16"
    0.469"0.922"0.047" to 0.077"-20180Black5090133A10400000
    1/2"
    0.490"1.062"0.062"-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A26000000
    1/2"
    0.490"1.062"0.078" to 0.108"-20180Black5090133A05300000
    1/2"
    0.490"1.062"0.110" to 0.140"-20180Black5090133A42500000
    9/16"
    0.594"1.156"0.047" to 0.077"-20180Black5090133A10500000
    5/8"
    0.615"1.312"0.078" to 0.108"-20180Black5090133A05600000
    5/8"
    0.615"1.312"0.110" to 0.140"-20180Black2590133A43000000
    3/4"
    0.740"1.500"0.062"-30220WhiteFDA Compliant 21 CFR 177.2600
    2590133A27000000
    3/4"
    0.740"1.500"0.078" to 0.108"-20180Black2590133A06000000
    3/4"
    0.740"1.500"0.110" to 0.140"-20180Black2590133A43500000
    7/8"
    0.938"1.750"0.078" to 0.108"-20180Black2590133A10600000
    1"
    0.990"2.000"0.078" to 0.108"-20180Black2590133A06400000
    1"
    0.990"2.000"0.110" to 0.140"-20180Black1090133A44000000
    1 1/8"
    1.187"2.250"0.105" to 0.145"-20180Black1090133A10700000
    1 1/4"
    1.375"2.500"0.105" to 0.145"-20180Black1090133A10800000
    1 1/2"
    1.437"3.000"0.105" to 0.145"-20180Black590133A10900000
    M3
    3.200 mm7.000 mm1.168 mm to 1.981 mm-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A61100000
    M4
    4.300 mm9.000 mm1.168 mm to 1.981 mm-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A61200000
    M5
    5.300 mm10.000 mm1.168 mm to 1.981 mm-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A61300000
    M6
    6.400 mm12.000 mm1.168 mm to 1.981 mm-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A61400000
    M8
    8.400 mm16.000 mm1.168 mm to 1.981 mm-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A61500000
    M10
    10.500 mm20.000 mm1.168 mm to 1.981 mm-30220WhiteFDA Compliant 21 CFR 177.2600
    5090133A61600000
    M12
    13.000 mm24.000 mm1.168 mm to 1.981 mm-30220WhiteFDA Compliant 21 CFR 177.2600
    2590133A61700000
    M14
    15.000 mm28.000 mm1.168 mm to 1.981 mm-30220WhiteFDA Compliant 21 CFR 177.2600
    2590133A61800000
    M16
    17.000 mm30.000 mm1.168 mm to 1.981 mm-30220WhiteFDA Compliant 21 CFR 177.2600
    1090133A61900000
    M18
    19.000 mm34.000 mm1.168 mm to 1.981 mm-30220WhiteFDA Compliant 21 CFR 177.2600
    1090133A62100000
    M20
    21.000 mm37.000 mm1.168 mm to 1.981 mm-30220WhiteFDA Compliant 21 CFR 177.2600
    1090133A62200000
    M22
    24.000 mm39.000 mm1.168 mm to 1.981 mm-30220WhiteFDA Compliant 21 CFR 177.2600
    1090133A62300000
    M24
    25.000 mm44.000 mm1.168 mm to 1.981 mm-30220WhiteFDA Compliant 21 CFR 177.2600
    590133A62400000
     
    Oil-Resistant Buna-N
    No. 2
    0.093"0.188"0.019" to 0.043"-30225WhiteFDA Compliant 21 CFR 177.2600
    5099082A1110000
    No. 4
    0.120"0.313"0.019" to 0.043"-30225WhiteFDA Compliant 21 CFR 177.2600
    5099082A1120000
     
    Weather-Resistant EPDM
    No. 6
    0.120"0.250"0.047" to 0.077"-20212Black10090130A0070000
    No. 8
    0.150"0.312"0.047" to 0.077"-20212Black10090130A0090000
    No. 10
    0.170"0.375"0.078" to 0.108"-20212Black10090130A0110000
    No. 12
    0.195"0.438"0.078" to 0.108"-20212Black10090130A01300000
    1/4"
    0.230"0.500"0.078" to 0.108"-20212Black10090130A02900000
    5/16"
    0.290"0.562"0.078" to 0.108"-20212Black10090130A03000000
    3/8"
    0.355"0.625"0.078" to 0.108"-20212Black10090130A03100000
    3/8"
    0.355"0.812"0.110" to 0.140"-20212Black2590130A1200000
    1/2"
    0.490"1.062"0.078" to 0.108"-20212Black10090130A03300000
    1/2"
    0.490"1.062"0.110" to 0.140"-20212Black2590130A1250000
    5/8"
    0.615"1.312"0.110" to 0.140"-20212Black2590130A1300000
    3/4"
    0.740"1.500"0.110" to 0.140"-20212Black2590130A13500000
    1"
    0.990"2.000"0.110" to 0.140"-20212Black1090130A1400000
     

    Chemical-Resistant Soft Fluoroelastomer Cord Stock

    Image of Product. Front orientation. Cord Stock. Chemical-Resistant Soft Fluoroelastomer Cord Stock.
    Softer and easier to compress than Viton® fluoroelastomer, this fluoroelastomer cord stock creates tighter seals on uneven surfaces. However, it’s also less wear resistant. It withstands a wide range of chemicals, including benzene, ethylene glycol, and boric acid. Since it won’t mar delicate surfaces, this cord stock is often used to seal laboratory flasks and aircraft altimeters.
    Per Ft.
    Wd.
    Wd. Tolerance Range
    Hardness
    ARPM
    Tolerance
    Specs.
    Met
    Temp. Range,
    ° F
    Color
    Choose a Length, ft.
    1-99
    100-Up
    0.040"-0.005" to 0.005"Durometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K510000000000
    0.063"-0.007" to 0.007"Durometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K5200000000
    0.070"-0.007" to 0.007"Durometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K7100000000
    0.094"-0.008" to 0.008"Durometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K5300000000
    0.103"-0.008" to 0.008"Durometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K7300000000
    0.125"-0.009" to 0.009"Durometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K5400000000
    0.139"-0.009" to 0.009"Durometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K7500000000
    0.188"-0.010" to 0.010"Durometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K5500000000
    0.210"-0.010" to 0.010"Durometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K7700000000
    0.250"-0.013" to 0.013"Durometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K5600000000
    0.275"-0.013" to 0.013"Durometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K7900000000
    0.313"-0.014" to 0.014"Durometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K8100000000
    0.375"-0.014" to 0.014"Durometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K83000000000
    0.437"-0.024" to 0.024"Durometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K850000000000
    0.500"-0.026" to 0.026"Durometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K870000000000
    1.000 mm-0.150 mm to 0.150 mmDurometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K5700000000
    2.000 mm-0.210 mm to 0.210 mmDurometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K5800000000
    3.000 mm-0.240 mm to 0.240 mmDurometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K5900000000
    4.000 mm-0.250 mm to 0.250 mmDurometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K6100000000
    5.000 mm-0.260 mm to 0.260 mmDurometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K6200000000
    6.000 mm-0.340 mm to 0.340 mmDurometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K6300000000
    7.000 mm-0.350 mm to 0.350 mmDurometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K6400000000
    8.000 mm-0.360 mm to 0.360 mmDurometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K6500000000
    9.000 mm-0.370 mm to 0.370 mmDurometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K6600000000
    10.000 mm-0.580 mm to 0.580 mmDurometer 55A (Soft)E2 PrecisionASTM D20005 to 395Black3, 10, 20, 50, 1007643K6700000000
    Make-Your-Own O-Ring Kits with Cord Stock
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