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    92 Products

    Center-Lock Distorted-Thread Locknuts
    3D CAD models available

    Image of Product. Front orientation. Locknuts. Center-Lock Distorted-Thread Locknuts.
    Also known as reversible locknuts, these thread on from either side, so you don't have to worry about fastening them incorrectly and damaging your screw. The irregularly shaped threads in the middle 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.
    High-Strength Steel
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength 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.
    Black-Oxide Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They offer minimal corrosion resistance, so they're best for dry environments.
    Zinc Flake-Coated Steel—The most durable zinc coating, these locknuts have a multilayer finish that resists wear for long-term rust protection. However, similar to zinc yellow-chromate-plated nuts, they won't hold up to harsh chemicals like stainless steel can.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc Yellow-Chromate-Plated Steel
    1/4"-20
    7/16"7/32"SAE Grade 8
    50000000000000000
    1/4"-28
    7/16"7/32"SAE Grade 8
    5000000000000000
    5/16"-18
    1/2"17/64"SAE Grade 8
    5000000000000000
    5/16"-24
    1/2"17/64"SAE Grade 8
    5000000000000000
    3/8"-16
    9/16"21/64"SAE Grade 8
    250000000000000
    3/8"-24
    9/16"21/64"SAE Grade 8
    2500000000000000
    7/16"-14
    11/16"3/8"SAE Grade 8
    100000000000000
    7/16"-20
    11/16"3/8"SAE Grade 8
    100000000000000
    1/2"-13
    3/4"7/16"SAE Grade 8
    100000000000000
    1/2"-20
    3/4"7/16"SAE Grade 8
    1000000000000000
    9/16"-12
    7/8"31/64"SAE Grade 8
    1000000000000000
    5/8"-11
    15/16"35/64"SAE Grade 8
    50000000000000
    5/8"-18
    15/16"35/64"SAE Grade 8
    50000000000000
    3/4"-10
    1 1/8"41/64"SAE Grade 8
    50000000000000
    3/4"-16
    1 1/8"41/64"SAE Grade 8
    500000000000000
    7/8"-9
    1 5/16"3/4"SAE Grade 8
    500000000000000
    1"-8
    1 1/2"55/64"SAE Grade 8
    10000000000000
    1"-14
    1 1/2"55/64"SAE Grade 8
    100000000000000
     
    Black-Oxide Steel
    1/4"-20
    7/16"7/32"SAE Grade 8
    100000000000000
    5/16"-18
    1/2"17/64"SAE Grade 8
    100000000000000
    3/8"-16
    9/16"21/64"SAE Grade 8
    100000000000000
    1/2"-13
    3/4"7/16"SAE Grade 8
    500000000000000
    5/8"-11
    15/16"35/64"SAE Grade 8
    10000000000000
    7/8"-9
    1 5/16"3/4"SAE Grade 8
    100000000000000
    1"-8
    1 1/2"55/64"SAE Grade 8
    100000000000000
    1"-14
    1 1/2"55/64"SAE Grade 8
    100000000000000
     
    Zinc Flake-Coated Steel
    1/4"-20
    7/16"7/32"SAE Grade 8
    100000000000000
    5/16"-18
    1/2"17/64"SAE Grade 8
    1000000000000000
    3/8"-16
    9/16"21/64"SAE Grade 8
    50000000000000
    1/2"-13
    3/4"7/16"SAE Grade 8
    500000000000000
    5/8"-11
    15/16"35/64"SAE Grade 8
    10000000000000
    1"-8
    1 1/2"55/64"SAE Grade 8
    100000000000000
     
    Medium-Strength Steel
    These Grade 5 or Class 8 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.
    Thread Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M5 × 0.8 mm8 mm4 mmISO Class 8
    10000000000000000
    M6 × 1 mm10 mm5 mmISO Class 8
    1000000000000000
    M7 × 1 mm11 mm5.5 mmISO Class 8
    50000000000000
    M8 × 1 mm13 mm6.5 mmISO Class 8
    1000000000000000
    M8 × 1.25 mm13 mm6.5 mmISO Class 8
    1000000000000000
    M10 × 1 mm17 mm8 mmISO Class 8
    50000000000000
    M10 × 1.25 mm17 mm8 mmISO Class 8
    50000000000000
    M10 × 1.5 mm17 mm8 mmISO Class 8
    1000000000000000
    M12 × 1.25 mm19 mm10 mmISO Class 8
    500000000000000
    M12 × 1.5 mm19 mm10 mmISO Class 8
    500000000000000
    M12 × 1.75 mm19 mm10 mmISO Class 8
    50000000000000
    M14 × 1.5 mm22 mm11 mmISO Class 8
    500000000000000
    M14 × 2 mm22 mm11 mmISO Class 8
    500000000000000
    M16 × 1.5 mm24 mm13 mmISO Class 8
    500000000000000
    M16 × 2 mm24 mm13 mmISO Class 8
    500000000000000
    M22 × 1.5 mm32 mm18 mmISO Class 8
    100000000000000
     
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-20
    7/16"7/32"SAE Grade 2
    10000000000000000
    1/4"-28
    7/16"7/32"SAE Grade 2
    10000000000000000
    5/16"-18
    1/2"17/64"SAE Grade 2
    1000000000000000
    5/16"-24
    1/2"17/64"SAE Grade 2
    1000000000000000
    3/8"-16
    9/16"21/64"SAE Grade 2
    10000000000000000
    3/8"-24
    9/16"21/64"SAE Grade 2
    10000000000000000
    7/16"-14
    11/16"3/8"SAE Grade 2
    5000000000000000
    7/16"-20
    11/16"3/8"SAE Grade 2
    5000000000000000
    1/2"-13
    3/4"7/16"SAE Grade 2
    5000000000000000
    1/2"-20
    3/4"7/16"SAE Grade 2
    5000000000000000
    5/8"-11
    15/16"35/64"SAE Grade 2
    2500000000000000
    5/8"-18
    15/16"35/64"SAE Grade 2
    2500000000000000
    3/4"-10
    1 1/8"41/64"SAE Grade 2
    1000000000000000
    3/4"-16
    1 1/8"41/64"SAE Grade 2
    1000000000000000
    1"-14
    1 1/2"55/64"SAE Grade 2
    500000000000000
     
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    316 Stainless Steel—Our most corrosion-resistant nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1/4"-20
    7/16"7/32"5000000000000000
    1/4"-28
    7/16"7/32"5000000000000000
    5/16"-18
    1/2"17/64"5000000000000000
    5/16"-24
    1/2"17/64"250000000000000
    3/8"-16
    9/16"21/64"250000000000000
    3/8"-24
    9/16"21/64"250000000000000
    7/16"-14
    11/16"3/8"100000000000000
    7/16"-20
    11/16"3/8"100000000000000
    1/2"-13
    3/4"7/16"100000000000000
    1/2"-20
    3/4"7/16"100000000000000
    5/8"-11
    15/16"35/64"50000000000000
    5/8"-18
    15/16"35/64"500000000000000
    3/4"-10
    1 1/8"41/64"500000000000000
    3/4"-16
    1 1/8"41/64"10000000000000
    7/8"-9
    1 5/16"3/4"10000000000000
    1"-8
    1 1/2"55/64"10000000000000
    1"-14
    1 1/2"55/64"10000000000000
     
    316 Stainless Steel
    1/4"-20
    7/16"7/32"100000000000000
    5/16"-18
    1/2"17/64"100000000000000
    3/8"-16
    9/16"21/64"100000000000000
    1/2"-13
    3/4"7/16"50000000000000
    5/8"-11
    15/16"35/64"10000000000000
    3/4"-10
    1 1/8"41/64"10000000000000
     

    Left-Hand-Thread Center-Lock Distorted-Thread Locknuts
    3D CAD models available

    Secure parts that rotate counterclockwise, such as the propeller on a mixer. Also known as reversible locknuts, these thread on from either side, so you don't have to worry about fastening them incorrectly and damaging your screw. The irregularly shaped threads in the middle 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.
    High-Strength Steel
    Image of Product. Front orientation. Contains Annotated, MultipleImages. Locknuts. Left-Hand-Thread Center-Lock Distorted-Thread Locknuts.
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength 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.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-20
    7/16"7/32"SAE Grade 8
    25000000000000000
    5/16"-18
    1/2"17/64"SAE Grade 8
    2500000000000000
    3/8"-16
    9/16"21/64"SAE Grade 8
    100000000000000
    1/2"-13
    3/4"7/16"SAE Grade 8
    1000000000000000
    5/8"-11
    15/16"35/64"SAE Grade 8
    500000000000000
    3/4"-10
    1 1/8"41/64"SAE Grade 8
    500000000000000
     
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