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    126 Products

    Distorted-Thread Flange Nuts
    3D CAD models available

    The strongest hold of all the flange nuts we offer, these have irregularly shaped threads that grip the screw to resist loosening. The threads prevent the nut from backing out due to high vibration, but they also increase the effort to install and remove. To get these nuts off, you may need special tools, such as an impact wrench or propane torch, so they are not reusable. Nuts have a flange that distributes pressure evenly across the mounting surface without the need for a separate washer. They are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. Also known as collar nuts.
    Medium-Strength Steel
    Image of Product. Bottom orientation. Flange Nuts. Distorted-Thread Flange Nuts.
    Rated Grade 5, Grade F, or Class 8, these nuts are your go-to for fastening most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Black Phosphate-Coated Steel—The dark coating creates both a finished appearance and a barrier against rust that's more durable than clear zinc plating.
    Flange
    Thread Size
    Wd.
    Ht.
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-20
    7/16"15/64"9/16"0.05"SAE Grade 5
    __10000000000000000
    5/16"-18
    1/2"9/32"11/16"0.05"SAE Grade 5
    __1000000000000000
    5/16"-24
    1/2"9/32"11/16"0.05"SAE Grade 5
    __1000000000000000
    3/8"-16
    9/16"11/32"3/4"0.06"SAE Grade 5
    __10000000000000000
    7/16"-14
    11/16"25/64"15/16"0.06"SAE Grade 5
    __5000000000000000
    7/16"-20
    11/16"25/64"15/16"0.06"SAE Grade 5
    __5000000000000000
    1/2"-13
    3/4"29/64"1 1/32"0.08"SAE Grade 5
    __5000000000000000
    1/2"-20
    3/4"29/64"1 1/32"0.08"SAE Grade 5
    __5000000000000000
    5/8"-11
    15/16"9/16"1 9/32"0.09"SAE Grade 5
    __100000000000000
    3/4"-10
    1 1/8"43/64"1 37/64"0.11"SAE Grade 5
    __100000000000000
    7/8"-9
    1 5/16"25/32"1 3/4"0.13"SAE Grade 5
    __500000000000000
    1"-8
    1 1/2"29/32"2 1/16"0.13"SAE Grade 5
    __10000000000000
    1"-14
    1 1/2"29/32"2 1/16"0.13"SAE Grade 5
    __10000000000000
    M5 × 0.8 mm8 mm6.2 mm11.8 mm1 mmISO Class 8
    DIN 6927500000000000000
    M6 × 1 mm10 mm7.3 mm14.2 mm1.1 mmISO Class 8
    DIN 69275000000000000000
    M8 × 1.25 mm13 mm9.4 mm17.9 mm1.2 mmISO Class 8
    DIN 69275000000000000000
    M10 × 1.25 mm15 mm11.4 mm21.8 mm1.5 mmISO Class 8
    DIN 69272500000000000000
    M10 × 1.5 mm15 mm11.4 mm21.8 mm1.5 mmISO Class 8
    DIN 6927250000000000000
    M12 × 1.75 mm18 mm13.8 mm26 mm1.8 mmISO Class 8
    DIN 69272500000000000000
    M16 × 2 mm24 mm18.3 mm34.5 mm2.4 mmISO Class 8
    DIN 69271000000000000000
     
    Black Phosphate-Coated Steel
    1/4"-20
    7/16"15/64"9/16"0.05"SAE Grade 5
    __1000000000000000
    5/16"-18
    1/2"9/32"11/16"0.05"SAE Grade 5
    __1000000000000000
    3/8"-16
    9/16"11/32"3/4"0.06"SAE Grade 5
    __10000000000000000
    7/16"-14
    11/16"25/64"15/16"0.06"SAE Grade 5
    __5000000000000000
    7/16"-20
    11/16"25/64"15/16"0.06"SAE Grade 5
    __5000000000000000
    1/2"-13
    3/4"29/64"1 1/32"0.08"SAE Grade 5
    __5000000000000000
    1/2"-20
    3/4"29/64"1 1/32"0.08"SAE Grade 5
    __5000000000000000
    5/8"-11
    15/16"9/16"1 9/32"0.09"SAE Grade 5
    __100000000000000
    3/4"-10
    1 1/8"43/64"1 37/64"0.11"SAE Grade 5
    __100000000000000
    1"-8
    1 1/2"29/32"2 1/16"0.13"SAE Grade 5
    __10000000000000
     
    High-Strength Steel
    Image of Product. Bottom orientation. Flange Nuts. Distorted-Thread Flange Nuts.
    Rated Grade 8, Grade G, or Class 10, these are about 25% stronger than medium-strength steel nuts. They are commonly used to fasten components in valves, pumps, and motors. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Zinc Yellow-Chromate-Plated Steel—With a more durable finish than clear zinc plating, these nuts are suitable for most wet and outdoor environments. However, they won't hold up to the harsh chemicals that stainless steel can.
    Black-Oxide Steel—Typically chosen for their appearance, these nuts have a dark, matte coating that creates a finished look. They offer minimal corrosion resistance, so they're best for dry environments.
    Black Phosphate-Coated Steel—The dark coating creates both a finished appearance and a barrier against rust that's more durable than clear zinc plating.
    Flange
    Thread Size
    Wd.
    Ht.
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M6 × 1 mm10 mm7.3 mm14.2 mm1.1 mmISO Class 10
    DIN 6927, EN 1664, ISO 7044500000000000000
    M8 × 1.25 mm13 mm9.4 mm17.9 mm1.2 mmISO Class 10
    DIN 6927, EN 1664, ISO 704425000000000000
    M10 × 1.5 mm15 mm11.4 mm21.8 mm1.5 mmISO Class 10
    DIN 6927, EN 1664, ISO 70441000000000000
    M12 × 1.75 mm18 mm13.8 mm26 mm1.8 mmISO Class 10
    DIN 6927, EN 1664, ISO 704410000000000000
    M14 × 2 mm21 mm15.9 mm29.9 mm2.1 mmISO Class 10
    DIN 6927, EN 1664, ISO 70445000000000000
    M16 × 2 mm24 mm18.3 mm34.5 mm2.4 mmISO Class 10
    DIN 6927, EN 1664, ISO 7044100000000000
    M20 × 2.5 mm30 mm22.4 mm42.8 mm3 mmISO Class 10
    DIN 6927, EN 1664, ISO 7044100000000000
     
    Zinc Yellow-Chromate-Plated Steel
    1/4"-20
    7/16"19/64"9/16"0.04"ASME Grade G
    __5000000000000000
    1/4"-28
    7/16"19/64"9/16"0.04"ASME Grade G
    __5000000000000000
    5/16"-18
    1/2"23/64"11/16"0.05"ASME Grade G
    __2500000000000000
    5/16"-24
    1/2"23/64"11/16"0.05"ASME Grade G
    __2500000000000000
    3/8"-16
    9/16"27/64"13/16"0.06"ASME Grade G
    __2500000000000000
    3/8"-24
    9/16"27/64"13/16"0.06"ASME Grade G
    __2500000000000000
    1/2"-13
    3/4"9/16"1 1/16"0.08"ASME Grade G
    __100000000000000
    1/2"-20
    3/4"9/16"1 1/16"0.08"ASME Grade G
    __1000000000000000
    5/8"-11
    15/16"11/16"1 21/64"0.1"ASME Grade G
    __1000000000000000
    5/8"-18
    15/16"11/16"1 21/64"0.1"ASME Grade G
    __1000000000000000
    3/4"-10
    1 1/8"13/16"1 37/64"0.11"ASME Grade G
    __500000000000000
     
    Black-Oxide Steel
    1/4"-20
    7/16"19/64"9/16"0.04"ASME Grade G
    __5000000000000000
    1/4"-28
    7/16"19/64"9/16"0.04"ASME Grade G
    __5000000000000000
    5/16"-18
    1/2"23/64"11/16"0.05"ASME Grade G
    __2500000000000000
    5/16"-24
    1/2"23/64"11/16"0.05"ASME Grade G
    __2500000000000000
    3/8"-16
    9/16"27/64"13/16"0.06"ASME Grade G
    __2500000000000000
    3/8"-24
    9/16"27/64"13/16"0.06"ASME Grade G
    __2500000000000000
    1/2"-13
    3/4"9/16"1 1/16"0.08"ASME Grade G
    __1000000000000000
    1/2"-20
    3/4"9/16"1 1/16"0.08"ASME Grade G
    __1000000000000000
    5/8"-11
    15/16"11/16"1 21/64"0.1"ASME Grade G
    __1000000000000000
    5/8"-18
    15/16"11/16"1 21/64"0.1"ASME Grade G
    __1000000000000000
    3/4"-10
    1 1/8"13/16"1 37/64"0.11"ASME Grade G
    __500000000000000
    M6 × 1 mm10 mm7.3 mm14.2 mm1.1 mmISO Class 10
    DIN 6927, EN 1664, ISO 70442500000000000
    M8 × 1.25 mm13 mm9.4 mm17.9 mm1.2 mmISO Class 10
    DIN 6927, EN 1664, ISO 70441000000000000
    M10 × 1.5 mm15 mm11.4 mm21.8 mm1.5 mmISO Class 10
    DIN 6927, EN 1664, ISO 70441000000000000
    M12 × 1.75 mm18 mm13.8 mm26 mm1.8 mmISO Class 10
    DIN 6927, EN 1664, ISO 70441000000000000
    M14 × 2 mm21 mm15.9 mm29.9 mm2.1 mmISO Class 10
    DIN 6927, EN 1664, ISO 7044500000000000
    M16 × 2 mm24 mm18.3 mm34.5 mm2.4 mmISO Class 10
    DIN 6927, EN 1664, ISO 7044100000000000
     
    Black Phosphate-Coated Steel
    1/4"-20
    7/16"19/64"9/16"0.04"ASME Grade G
    __1000000000000000
    1/4"-28
    7/16"19/64"9/16"0.04"ASME Grade G
    __1000000000000000
    5/16"-18
    1/2"23/64"11/16"0.05"ASME Grade G
    __10000000000000000
    5/16"-24
    1/2"23/64"11/16"0.05"ASME Grade G
    __10000000000000000
    3/8"-16
    9/16"27/64"13/16"0.06"ASME Grade G
    __5000000000000000
    3/8"-24
    9/16"27/64"13/16"0.06"ASME Grade G
    __2500000000000000
    1/2"-13
    3/4"9/16"1 1/16"0.08"ASME Grade G
    __2500000000000000
    1/2"-20
    3/4"9/16"1 1/16"0.08"ASME Grade G
    __250000000000000
    5/8"-11
    15/16"11/16"1 21/64"0.1"ASME Grade G
    __1000000000000000
    5/8"-18
    15/16"11/16"1 21/64"0.1"ASME Grade G
    __100000000000000
    3/4"-10
    1 1/8"53/64"1 37/64"0.11"ASME Grade G
    __1000000000000000
    3/4"-16
    1 1/8"53/64"1 37/64"0.11"ASME Grade G
    __100000000000000
    7/8"-9
    1 5/16"51/64"1 3/4"0.12"ASME Grade G
    __500000000000000
    7/8"-14
    1 5/16"51/64"1 3/4"0.12"ASME Grade G
    __500000000000000
    1"-8
    1 1/2"57/64"2 1/16"0.13"ASME Grade G
    __500000000000000
    1"-14
    1 1/2"57/64"2 1/16"0.13"ASME Grade G
    __500000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Bottom orientation. Flange Nuts. Distorted-Thread Flange Nuts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    6-32
    5/16"11/64"0.422"0.02"500000000000000
    8-32
    11/32"13/64"0.469"0.02"50000000000000
    10-24
    3/8"7/32"0.5"0.03"50000000000000
    10-32
    3/8"7/32"0.5"0.03"50000000000000
    12-24
    7/16"15/64"0.594"0.04"500000000000000
    1/4"-20
    7/16"15/64"0.594"0.04"100000000000000
    1/4"-28
    7/16"15/64"0.594"0.04"10000000000000
    5/16"-18
    1/2"9/32"0.68"0.04"100000000000000
    3/8"-16
    9/16"11/32"0.75"0.04"100000000000000
    3/8"-24
    9/16"11/32"0.75"0.04"10000000000000
    1/2"-13
    3/4"29/64"1.031"0.04"50000000000000
    1/2"-20
    3/4"29/64"1.031"0.05"10000000000000
     

    Mil. Spec. Distorted-Thread Flange Nuts
    3D CAD models available

    Not only do these have the strongest hold of all the flange nuts we offer, they are also manufactured and tested to strict U.S. military standards for material and construction. They have irregularly shaped threads that grip the screw to resist loosening in high-vibration applications. The threads prevent the nut from backing out, but they also increase the effort to install and remove. To get these nuts off, you may need special tools, such as an impact wrench or propane torch, so they are not reusable. Nuts have a flange that distributes pressure evenly across the mounting surface without the need for a separate washer. They are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. Also known as collar nuts.
    Low-Strength Steel
    Image of Product. Front orientation. Flange Nuts. Mil. Spec. Distorted-Thread Flange Nuts.
    About half the strength of medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Cadmium-Plated Steel—The plating reduces friction during installation, so these nuts thread on smoother than others. It also creates a barrier against rust that's comparable to zinc yellow-chromate plating.
    Cadmium Yellow-Chromate-Plated Steel—Better corrosion resistance than plain cadmium. These nuts withstand salt water and are suitable for most wet and outdoor environments.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Mil. Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    2-56
    1/8"3/32"0.167"0.01"MS21042L025000000000000000
    4-40
    5/32"1/8"0.206"0.03"MS21042L0450000000000000
    6-32
    3/16"9/64"0.244"0.03"MS21042L0650000000000000
    8-32
    7/32"3/16"0.29"0.03"MS21042L0850000000000000
    10-32
    1/4"3/16"0.33"0.03"MS21042L350000000000000
    1/4"-28
    5/16"7/32"0.42"0.04"MS21042L450000000000000
    5/16"-24
    3/8"17/64"0.52"0.04"MS21042L510000000000000
    3/8"-24
    7/16"9/32"0.62"0.04"MS21042L610000000000000
     
    Cadmium Yellow-Chromate-Plated Steel
    2-56
    1/8"3/32"0.167"0.01"MS21042-02500000000000000
    4-40
    5/32"1/8"0.206"0.03"MS21042-0450000000000000
    6-32
    3/16"9/64"0.244"0.03"MS21042-0650000000000000
    8-32
    7/32"3/16"0.29"0.03"MS21042-0850000000000000
    10-32
    1/4"3/16"0.33"0.03"MS21042-350000000000000
    1/4"-28
    5/16"7/32"0.42"0.04"MS21042-450000000000000
    5/16"-24
    3/8"17/64"0.52"0.04"MS21042-510000000000000
    3/8"-24
    7/16"9/32"0.62"0.04"MS21042-610000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Flange Nuts. Mil. Spec. Distorted-Thread Flange Nuts.
    High-Temperature A286 Stainless Steel—Stronger than 316 stainless steel and withstand high temperatures up to 1500° F. These nuts resist corrosion from chemicals, such as bleach and chlorine, but they won't hold up to salt water as well as 316 stainless steel.
    High-Temperature Silver-Plated A286 Stainless Steel—The silver plating reduces friction during installation, so these nuts thread on smoother than others. They are stronger than 316 stainless steel and withstand temperatures up to 800° F. Nuts resist corrosion from chemicals, such as bleach and chlorine, but won't hold up to salt water as well as 316 stainless steel.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Mil. Specs.
    Met
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    High-Temperature A286 Stainless Steel
    2-56
    1/8"3/32"0.167"0.01"__NAS1291C02M5000000000000000
    4-40
    5/32"1/8"0.206"0.01"__NAS1291C04M10000000000000
    6-32
    3/16"9/64"0.244"0.01"__NAS1291C06M10000000000000
    8-32
    7/32"3/16"0.29"0.02"__NAS1291C08M10000000000000
    10-32
    1/4"3/16"0.33"0.02"__NAS1291C3M10000000000000
    1/4"-28
    5/16"7/32"0.42"0.02"__NAS1291C4M10000000000000
    5/16"-24
    3/8"17/64"0.52"0.03"__NAS1291C5M10000000000000
    3/8"-24
    7/16"9/32"0.62"0.03"__NAS1291C6M100000000000000
    7/16"-20
    1/2"21/64"0.708"0.04"__NAS1291C7M100000000000000
    1/2"-20
    9/16"13/32"0.814"0.04"__NAS1291C8M100000000000000
     
    High-Temperature Silver-Plated A286 Stainless Steel
    4-40
    5/32"1/8"0.206"0.03"MS21043-04__500000000000000
    6-32
    3/16"9/64"0.244"0.03"MS21043-06__50000000000000
    8-32
    7/32"3/16"0.29"0.03"MS21043-08__500000000000000
    10-32
    1/4"3/16"0.33"0.03"MS21043-3__50000000000000
    1/4"-28
    5/16"7/32"0.42"0.04"MS21043-4__500000000000000
    5/16"-24
    3/8"17/64"0.52"0.04"MS21043-5__10000000000000
    3/8"-24
    7/16"9/32"0.62"0.04"MS21043-6__10000000000000
     
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