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    33 Products

    Washers for Square-Neck Bolts
    3D CAD models available

    These washers fit snugly around carriage, plow, and elevator bolts to distribute pressure evenly. The square hole also stops the washer from spinning during installation, so it stays aligned with the bolt for a sturdy connection.
    Stainless Steel
    Image of Product. Without Prongs. Front orientation. Washers. Washers for Square-Neck Bolts.

    Without Prongs

    18-8 Stainless Steel—The choice for wet and outdoor environments, these washers resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    For Screw
    Size
    Inside
    Wd.
    OD
    Thk.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    No. 10
    		0.204"0.437"0.025" to 0.035"50000000000000000
    No. 10
    		0.226"0.500"0.043" to 0.053"5000000000000000
    No. 10
    		0.253"0.561"0.028" to 0.034"5000000000000000
    1/4"
    		0.320"0.680"0.055" to 0.065"2500000000000000
    5/16"
    		0.385"0.750"0.043" to 0.053"2500000000000000
    3/8"
    		0.392"0.900"0.085" to 0.095"1000000000000000
    3/8"
    		0.405"0.700"0.055" to 0.065"2500000000000000
    7/16"
    		0.517"0.937"0.055" to 0.065"2500000000000000
    1/2"
    		0.555"1.000"0.055" to 0.065"1000000000000000
    1/2"
    		0.617"1.125"0.055" to 0.065"1000000000000000
    5/8"
    		0.650"1.500"0.115" to 0.125"500000000000000
    5/8"
    		0.700"1.250"0.055" to 0.065"1000000000000000
    3/4"
    		0.812"1.375"0.055" to 0.065"50000000000000
     
    Steel
    Image of Product. Without Prongs. Front orientation. Washers. Washers for Square-Neck Bolts.

    Without Prongs

    Zinc-Plated Steel—A common choice for areas with occasional exposure to moisture.
    For Screw
    Size
    Inside
    Wd.
    OD
    Thk.
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    No. 10
    		0.204"0.437"0.025" to 0.035"25000000000000000
    No. 10
    		0.226"0.500"0.043" to 0.053"2500000000000000
    No. 10
    		0.253"0.561"0.028" to 0.034"2500000000000000
    1/4"
    		0.320"0.680"0.055" to 0.065"2500000000000000
    5/16"
    		0.385"0.750"0.043" to 0.053"2500000000000000
    3/8"
    		0.392"0.900"0.085" to 0.095"2500000000000000
    3/8"
    		0.405"0.700"0.055" to 0.065"2500000000000000
    7/16"
    		0.517"0.937"0.055" to 0.065"2500000000000000
    1/2"
    		0.555"1.000"0.055" to 0.065"2500000000000000
    1/2"
    		0.617"1.125"0.055" to 0.065"2500000000000000
    5/8"
    		0.650"1.500"0.115" to 0.125"2500000000000000
    5/8"
    		0.700"1.250"0.055" to 0.065"2500000000000000
    3/4"
    		0.812"1.375"0.055" to 0.065"1000000000000000
     
    Steel with Prongs
    Image of Product. With Prongs. Front orientation. Washers. Washers for Square-Neck Bolts, Prongs.

    With Prongs

    The prongs dig into wood and other soft materials to hold the washer in place.
    Zinc-Plated Steel—A common choice for areas with occasional exposure to moisture.
    For Screw
    Size
    Inside
    Wd.
    OD
    Thk.
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"
    		0.270"1.100"0.044" to 0.051"1000000000000000
    5/16"
    		0.345"1.100"0.041" to 0.053"100000000000000
    3/8"
    		0.405"1.100"0.042" to 0.051"100000000000000
    1/2"
    		0.535"1.750"0.057" to 0.069"50000000000000
     

    Washers for Foam Insulation
    3D CAD models available

    Mount insulation board to foundation walls, roofing, and framing. These washers have a large surface that distributes holding pressure evenly, so they won't crush or pull through insulation.
    Polypropylene ​​​​​​​​ ​with Prongs
    Image of Product. Perforated. Front orientation. Contains Border, MultipleImages. Washers. Washers for Foam Insulation, Polypropylene ​​​​​​​​ ​with Prongs, Perforated.
    Image of Product. Solid. Front orientation. Contains Border, MultipleImages. Washers. Washers for Foam Insulation, Polypropylene ​​​​​​​​ ​with Prongs, Solid.

    Perforated

    Solid

    Prongs sink into rigid insulation and hold the washer in place, so it won't shift during installation.
    Perforated—These economical washers are best for interior applications.
    Solid—When fastened, these washers flex to create a seal around the connection that blocks out air and moisture. They are most often used on exterior walls to attach weather barriers over insulation.
    Temp.
    Range
    For Screw
    Size
    ID
    OD
    Thk.
    Min.
    Max.,
    ° F
    Color
    Pkg.
    Qty.
    Pkg.
    Perforated
    No. 10
    		0.190"1.750"0.180"Not Rated150White5000000000000000
     
    Solid
    No. 10
    		0.190"2.000"0.220"Not Rated150Black250000000000000
     

    Perforated Washers
    3D CAD models available

    Image of Product. With Prongs. Front orientation. Washers. Perforated Washers, Corrosion-Resistant Galvanized Steel, Prongs.

    With Prongs

    Plaster and grout flow through the perforations in these washers to form a secure bond between the washer and the wall. Use them under drywall screws to fasten cracked, sagging plaster back onto lath and to secure wire mesh to backer board before installing tile.
    Corrosion-Resistant Galvanized Steel—These washers combine the strength of steel with the rust resistance of stainless steel. They're an economical alternative to 18-8 stainless steel in wet and outdoor environments, but they won't hold up to salt water and chemicals.
    Prongs—The prongs sink into lath, backer board, and other soft materials to hold the washer in place, so it won't shift during installation.
    For Screw
    Size
    ID
    OD
    Thk.
    Features
    Prong
    Lg.
    Pkg.
    Qty.
    Pkg.
    Corrosion-Resistant Galvanized Steel
    No. 8
    		0.175"1.250"0.020" to 0.024"Prongs5/16"50000000000000000
     
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