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    149 Products

    Nylon-Insert Locknuts

    Versatile yet economical, these are the most commonly used locknuts. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    High-Strength Steel
    Image of Product. Front orientation. Locknuts. Nylon-Insert Locknuts.
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength steel nuts. 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-Corrosion-Resistant-Coated Steel—These nuts combine a finished appearance with the rust resistance of stainless steel. The coating has been tested to extreme standards, including 1,000 hours of salt spray resistance, to hold up in wet and outdoor environments. Also known as black luster.
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M4 × 0.7 mm75ISO Class 10
    220DIN 985100000000000000000
    M5 × 0.8 mm85ISO Class 10
    220DIN 98510000000000000000
    M6 × 1 mm106ISO Class 10
    220DIN 98510000000000000000
    M8 × 1 mm138ISO Class 10
    220DIN 985, ISO 105111000000000000000
    M8 × 1.25 mm138ISO Class 10
    220DIN 9855000000000000000
    M10 × 1 mm1710ISO Class 10
    220DIN 985, ISO 105112500000000000000
    M10 × 1.25 mm1710ISO Class 10
    220DIN 985, ISO 105111000000000000000
    M10 × 1.5 mm1710ISO Class 10
    220DIN 9852500000000000000
    M12 × 1.25 mm1912ISO Class 10
    220DIN 985, ISO 105111000000000000000
    M12 × 1.5 mm1912ISO Class 10
    220DIN 985, ISO 105111000000000000000
    M12 × 1.75 mm1912ISO Class 10
    220DIN 9851000000000000000
    M14 × 1.5 mm2214ISO Class 10
    220DIN 985, ISO 10511500000000000000
    M14 × 2 mm2214ISO Class 10
    220DIN 9851000000000000000
    M16 × 1.5 mm2416ISO Class 10
    220DIN 985, ISO 1051110000000000000
    M16 × 2 mm2416ISO Class 10
    220DIN 9851000000000000000
    M18 × 1.5 mm2718ISO Class 10
    220DIN 985, ISO 1051110000000000000
    M18 × 2.5 mm2718.5ISO Class 10
    220DIN 985500000000000000
    M20 × 1.5 mm3020ISO Class 10
    220DIN 985, ISO 1051110000000000000
    M20 × 2 mm3020ISO Class 10
    220DIN 985, ISO 10511100000000000000
    M20 × 2.5 mm3020ISO Class 10
    220DIN 985500000000000000
    M22 × 1.5 mm3222ISO Class 10
    220DIN 985, ISO 10511100000000000000
    M22 × 2.5 mm3222ISO Class 10
    220DIN 98510000000000000
    M24 × 1.5 mm3624ISO Class 10
    220DIN 985, ISO 10511100000000000000
    M24 × 2 mm3624ISO Class 10
    220DIN 985, ISO 10511100000000000000
    M24 × 3 mm3624ISO Class 10
    220DIN 98510000000000000
    M27 × 3 mm4127ISO Class 10
    220DIN 985100000000000000
    M30 × 2 mm4630ISO Class 10
    220DIN 985, ISO 10511100000000000000
    M30 × 3.5 mm4630ISO Class 10
    220DIN 985100000000000000
    M33 × 3.5 mm5033ISO Class 10
    220DIN 985100000000000000
    M36 × 3 mm5536ISO Class 10
    220DIN 985, ISO 10511100000000000000
    M36 × 4 mm5536ISO Class 10
    220DIN 985100000000000000
    M39 × 4 mm6039ISO Class 10
    220DIN 985100000000000000
    M42 × 4.5 mm6542ISO Class 10
    220DIN 985100000000000000
     
    Black-Corrosion-Resistant-Coated Steel
    M4 × 0.7 mm75ISO Class 10
    220DIN 985500000000000000
    M5 × 0.8 mm85ISO Class 10
    220DIN 985500000000000000
    M6 × 1 mm106ISO Class 10
    220DIN 985500000000000000
    M8 × 1.25 mm138ISO Class 10
    220DIN 985500000000000000
    M10 × 1.5 mm1710ISO Class 10
    220DIN 985500000000000000
    M12 × 1.75 mm1912ISO Class 10
    220DIN 98510000000000000
    M14 × 2 mm2214ISO Class 10
    220DIN 98510000000000000
     

    High-Profile Nylon-Insert Locknuts

    Slightly taller than standard-profile locknuts, these have a larger gripping area so your wrench or socket won't slip off as you tighten them. They're often used in vehicles and machinery where fasteners can be difficult to reach. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    High-Strength Steel
    Image of Product. Front orientation. Locknuts. High-Profile Nylon-Insert Locknuts.
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength steel nuts. 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.
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M6 × 1 mm108ISO Class 10
    220DIN 98250000000000000000
    M8 × 1.25 mm139.5ISO Class 10
    220DIN 982250000000000000
    M10 × 1.5 mm1711.5ISO Class 10
    220DIN 9822500000000000000
    M12 × 1.75 mm1914ISO Class 10
    220DIN 9821000000000000000
    M14 × 2 mm2216ISO Class 10
    220DIN 9821000000000000000
    M16 × 2 mm2418ISO Class 10
    220DIN 982500000000000000
    M18 × 2.5 mm2720ISO Class 10
    220DIN 982500000000000000
    M20 × 2.5 mm3022ISO Class 10
    220DIN 98210000000000000
    M24 × 3 mm3628ISO Class 10
    220DIN 98210000000000000
     

    Top-Lock Distorted-Thread Locknuts

    Irregularly shaped threads at the top of these locknuts grip the screw for a stronger hold than nylon-insert locknuts. Although the threads prevent the nut from backing out due to vibration, 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. Nuts are not reusable.
    High-Strength Steel
    Image of Product. Front orientation. Locknuts. Top-Lock Distorted-Thread Locknuts.
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    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.
    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 comparable to zinc yellow-chromate plating.
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Yellow-Chromate-Plated Steel
    M6 × 1 mm106ISO Class 10
    100000000000000000
    M8 × 1 mm138ISO Class 10
    100000000000000
    M8 × 1.25 mm138ISO Class 10
    5000000000000000
    M10 × 1.25 mm1710ISO Class 10
    100000000000000
    M10 × 1.5 mm1710ISO Class 10
    2500000000000000
    M12 × 1.25 mm1912ISO Class 10
    500000000000000
    M12 × 1.5 mm1912ISO Class 10
    500000000000000
    M12 × 1.75 mm1912ISO Class 10
    100000000000000
    M14 × 1.5 mm2214ISO Class 10
    500000000000000
    M14 × 2 mm2214ISO Class 10
    100000000000000
    M16 × 1.5 mm2416ISO Class 10
    10000000000000
    M16 × 2 mm2416ISO Class 10
    1000000000000000
    M18 × 2.5 mm2718ISO Class 10
    500000000000000
    M20 × 2.5 mm3020ISO Class 10
    500000000000000
    M24 × 3 mm3624ISO Class 10
    10000000000000
     
    Zinc-Plated Steel
    M5 × 0.8 mm85.1ISO Class 10
    1000000000000000
    M6 × 1 mm106ISO Class 10
    10000000000000000
    M8 × 1 mm138ISO Class 10
    5000000000000000
    M8 × 1.25 mm138ISO Class 10
    500000000000000
    M10 × 1 mm1710ISO Class 10
    2500000000000000
    M10 × 1.25 mm1710ISO Class 10
    1000000000000000
    M10 × 1.5 mm1710ISO Class 10
    2500000000000000
    M12 × 1.25 mm1912ISO Class 10
    2500000000000000
    M12 × 1.5 mm1912ISO Class 10
    1000000000000000
    M12 × 1.75 mm1912ISO Class 10
    2500000000000000
    M14 × 1.5 mm2214ISO Class 10
    100000000000000
    M14 × 2 mm2214ISO Class 10
    100000000000000
    M16 × 1.5 mm2416ISO Class 10
    1000000000000000
    M16 × 2 mm2416ISO Class 10
    100000000000000
    M18 × 1.5 mm2718ISO Class 10
    50000000000000
    M18 × 2.5 mm2718ISO Class 10
    50000000000000
    M20 × 1.5 mm3020ISO Class 10
    500000000000000
    M20 × 2.5 mm3020ISO Class 10
    500000000000000
    M22 × 1.5 mm3222ISO Class 10
    500000000000000
    M22 × 2.5 mm3222ISO Class 10
    500000000000000
    M24 × 1.5 mm3624ISO Class 10
    10000000000000
    M24 × 3 mm3624ISO Class 10
    10000000000000
    M27 × 3 mm4127ISO Class 10
    10000000000000
    M30 × 2 mm4630ISO Class 10
    10000000000000
    M30 × 3.5 mm4630ISO Class 10
    10000000000000
     
    Black-Phosphate-Coated Steel
    M5 × 0.8 mm85.1ISO Class 10
    5000000000000000
    M6 × 1 mm106ISO Class 10
    250000000000000
    M8 × 1 mm138ISO Class 10
    100000000000000
    M8 × 1.25 mm138ISO Class 10
    2500000000000000
    M10 × 1.25 mm1710ISO Class 10
    500000000000000
    M10 × 1.5 mm1710ISO Class 10
    1000000000000000
    M12 × 1.25 mm1912ISO Class 10
    500000000000000
    M12 × 1.5 mm1912ISO Class 10
    500000000000000
    M12 × 1.75 mm1912ISO Class 10
    50000000000000
    M14 × 1.5 mm2214ISO Class 10
    500000000000000
    M14 × 2 mm2214ISO Class 10
    500000000000000
    M16 × 1.5 mm2416ISO Class 10
    10000000000000
    M16 × 2 mm2416ISO Class 10
    500000000000000
    M20 × 2.5 mm3020ISO Class 10
    10000000000000
    M22 × 1.5 mm3322ISO Class 10
    10000000000000
    M22 × 2.5 mm3322ISO Class 10
    10000000000000
     

    Serrated Flange Nuts

    Serrations bite into material for mild vibration resistance while the flange eliminates the need for a separate washer. These nuts are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. You can use them again and again without sacrificing strength. However, the serrations may mar the surface of your material. Also known as collar nuts.
    High-Strength Steel
    Image of Product. Bottom orientation. Flange Nuts. Serrated 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.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Flange,
    mm
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M5 × 0.8 mm8511.81ISO Class 10
    DIN 69232500000000000000
    M6 × 1 mm10614.21.1ISO Class 10
    DIN 69235000000000000000
    M8 × 1.25 mm13817.91.2ISO Class 10
    DIN 69235000000000000000
    M10 × 1.5 mm151021.81.5ISO Class 10
    DIN 69232500000000000000
    M12 × 1.75 mm1812261.8ISO Class 10
    DIN 6923100000000000000
    M16 × 2 mm241634.52.4ISO Class 10
    DIN 6923500000000000000
    M20 × 2.5 mm302042.83ISO Class 10
    DIN 692310000000000000
     
    Steel
    M5 × 0.8 mm8511.81ISO Class 10
    DIN 6923250000000000000
    M6 × 1 mm10614.21.1ISO Class 10
    DIN 69235000000000000000
    M8 × 1.25 mm13817.91.2ISO Class 10
    DIN 69235000000000000000
    M10 × 1.5 mm151021.81.5ISO Class 10
    DIN 69232500000000000000
    M12 × 1.75 mm1812261.8ISO Class 10
    DIN 69231000000000000000
    M16 × 2 mm241634.52.4ISO Class 10
    DIN 6923500000000000000
    M20 × 2.5 mm302042.83ISO Class 10
    DIN 692310000000000000
     

    Nylon-Insert Flange Nuts

    A nylon insert grips the screw for a stronger hold than a serrated flange, without damaging threads or marring the surface of your material. However, the insert may become brittle if exposed to high temperatures. These nuts have a flange that distributes pressure evenly across the mounting surface, so you don't need 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. You can reuse them a handful of times, but their holding power will decrease with each use. Also known as collar nuts.
    High-Strength Steel
    Image of Product. Front orientation. Flange Nuts. Nylon-Insert 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.
    Flange,
    mm
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M6 × 1 mm109.114.21.1ISO Class 10
    DIN 692625025000000000000000
    M8 × 1.25 mm1311.117.91.2ISO Class 10
    DIN 6926250100000000000000
    M10 × 1.25 mm1513.521.81.5ISO Class 10
    DIN 6926250500000000000000
    M10 × 1.5 mm1513.521.81.5ISO Class 10
    DIN 69262501000000000000000
    M12 × 1.25 mm1816.1261.8ISO Class 10
    DIN 692625010000000000000
    M12 × 1.5 mm1816.1261.8ISO Class 10
    DIN 692625010000000000000
    M12 × 1.75 mm1816.1261.8ISO Class 10
    DIN 6926250500000000000000
    M14 × 1.5 mm2118.229.92.1ISO Class 10
    DIN 692625010000000000000
    M14 × 2 mm2118.229.92.1ISO Class 10
    DIN 692625010000000000000
    M16 × 2 mm2420.334.52.4ISO Class 10
    DIN 692625010000000000000
     
    Zinc-Yellow-Chromate-Plated Steel
    M6 × 1 mm109.114.21.1ISO Class 10
    DIN 69262505000000000000000
    M8 × 1.25 mm131117.91.2ISO Class 10
    DIN 69262505000000000000000
    M10 × 1.5 mm1513.521.81.5ISO Class 10
    DIN 69262502500000000000000
    M12 × 1.75 mm1816.1261.8ISO Class 10
    DIN 69262502500000000000000
    M14 × 2 mm2118.229.92.1ISO Class 10
    DIN 69262501000000000000000
    M16 × 2 mm2420.334.52.4ISO Class 10
    DIN 6926250500000000000000
    M20 × 2.5 mm3024.842.83ISO Class 10
    DIN 692625010000000000000
     

    Distorted-Thread Flange Nuts

    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.
    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.
    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.
    Flange,
    mm
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M6 × 1 mm107.314.21.1ISO Class 10
    DIN 6927, EN 1664, ISO 7044500000000000000
    M8 × 1.25 mm139.417.91.2ISO Class 10
    DIN 6927, EN 1664, ISO 704425000000000000
    M10 × 1.5 mm1511.421.81.5ISO Class 10
    DIN 6927, EN 1664, ISO 70441000000000000
    M12 × 1.75 mm1813.8261.8ISO Class 10
    DIN 6927, EN 1664, ISO 704410000000000000
    M14 × 2 mm2115.929.92.1ISO Class 10
    DIN 6927, EN 1664, ISO 70445000000000000
    M16 × 2 mm2418.334.52.4ISO Class 10
    DIN 6927, EN 1664, ISO 7044100000000000
    M20 × 2.5 mm3022.442.83ISO Class 10
    DIN 6927, EN 1664, ISO 7044100000000000
     
    Black-Oxide Steel
    M6 × 1 mm107.314.21.1ISO Class 10
    DIN 6927, EN 1664, ISO 70442500000000000
    M8 × 1.25 mm139.417.91.2ISO Class 10
    DIN 6927, EN 1664, ISO 70441000000000000
    M10 × 1.5 mm1511.421.81.5ISO Class 10
    DIN 6927, EN 1664, ISO 70441000000000000
    M12 × 1.75 mm1813.8261.8ISO Class 10
    DIN 6927, EN 1664, ISO 70441000000000000
    M14 × 2 mm2115.929.92.1ISO Class 10
    DIN 6927, EN 1664, ISO 7044500000000000
    M16 × 2 mm2418.334.52.4ISO Class 10
    DIN 6927, EN 1664, ISO 7044100000000000
     
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