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    185 Products

    Flex-Top Locknuts for Heavy Vibration
    3D CAD models available

    Image of Product. Front orientation. Locknuts. Flex-Top Locknuts for Heavy Vibration.
    The top section of these nuts expands to grip the screw on all sides for a stronger hold than both nylon-insert and distorted-thread locknuts. They’re often used in equipment with constant, vigorous vibration, such as engines. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Steel
    These locknuts have equivalent strength to Grade 8 and Class 10 steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    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.
    Cadmium-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc-yellow-chromate plating.
    Thread Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Black-Oxide Steel
    1/4"-20
    7/16"19/64"500000000000000
    1/4"-28
    7/16"5/16"50000000000000
    5/16"-18
    1/2"23/64"50000000000000
    5/16"-24
    1/2"23/64"50000000000000
    3/8"-16
    9/16"15/32"50000000000000
    3/8"-24
    9/16"15/32"50000000000000
    7/16"-14
    5/8"15/32"10000000000000
    1/2"-13
    3/4"39/64"10000000000000
    1/2"-20
    3/4"39/64"10000000000000
    5/8"-11
    15/16"49/64"10000000000000
    5/8"-18
    15/16"49/64"10000000000000
    3/4"-10
    1 1/16"57/64"100000000000000
    3/4"-16
    1 1/16"57/64"10000000000000
    M6 × 1 mm10 mm7.8 mm10000000000000
    M8 × 1.25 mm13 mm10.4 mm10000000000000
    M10 × 1.5 mm17 mm13 mm10000000000000
    M12 × 1.75 mm19 mm15.6 mm100000000000000
     
    Cadmium-Plated Steel
    4-40
    1/4"5/32"1000000000000000
    6-32
    5/16"3/16"2500000000000000
    8-32
    11/32"1/4"2500000000000000
    10-24
    3/8"1/4"2500000000000000
    10-32
    3/8"1/4"2500000000000000
    1/4"-20
    7/16"19/64"2500000000000000
    1/4"-28
    7/16"5/16"2500000000000000
    5/16"-18
    1/2"23/64"100000000000000
    5/16"-24
    1/2"23/64"100000000000000
    3/8"-16
    9/16"15/32"1000000000000000
    3/8"-24
    9/16"15/32"1000000000000000
    7/16"-14
    5/8"15/32"500000000000000
    7/16"-20
    5/8"15/32"10000000000000
    1/2"-13
    3/4"39/64"500000000000000
    1/2"-20
    3/4"39/64"500000000000000
    9/16"-18
    7/8"31/64"100000000000000
    5/8"-11
    15/16"49/64"10000000000000
    5/8"-18
    15/16"49/64"10000000000000
    3/4"-10
    1 1/16"57/64"10000000000000
    3/4"-16
    1 1/16"57/64"10000000000000
    7/8"-9
    1 1/4"1 1/64"100000000000000
    7/8"-14
    1 1/4"1 1/64"100000000000000
    1"-8
    1 7/16"1 9/64"100000000000000
    1"-14
    1 7/16"1 9/64"100000000000000
    M6 × 1 mm10 mm7.8 mm500000000000000
    M8 × 1.25 mm13 mm10.4 mm10000000000000
    M10 × 1.5 mm17 mm13 mm100000000000000
    M12 × 1.75 mm19 mm15.6 mm100000000000000
     
    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.
    Black-Oxide 18-8 Stainless Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They resist rust in wet and outdoor environments, but 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
    2-56
    1/4"5/32"5000000000000000
    6-32
    5/16"3/16"50000000000000
    8-32
    11/32"1/4"50000000000000
    10-24
    3/8"1/4"50000000000000
    10-32
    3/8"1/4"1000000000000000
    1/4"-20
    7/16"19/64"500000000000000
    1/4"-28
    7/16"19/64"50000000000000
    5/16"-18
    1/2"23/64"10000000000000
    5/16"-24
    1/2"23/64"10000000000000
    3/8"-16
    9/16"15/32"10000000000000
    3/8"-24
    9/16"15/32"10000000000000
    7/16"-20
    5/8"15/32"100000000000000
    1/2"-13
    3/4"39/64"10000000000000
    1/2"-20
    3/4"39/64"10000000000000
    M3 × 0.5 mm5.5 mm4.5 mm10000000000000
    M4 × 0.7 mm7 mm6 mm10000000000000
    M5 × 0.8 mm8 mm7.5 mm10000000000000
    M6 × 1 mm10 mm7.8 mm10000000000000
    M8 × 1.25 mm13 mm10.4 mm10000000000000
    M10 × 1.5 mm17 mm13 mm100000000000000
    M12 × 1.75 mm19 mm15.6 mm100000000000000
    M14 × 2 mm22 mm18.2 mm100000000000000
    M16 × 2 mm24 mm20.8 mm100000000000000
    M18 × 2.5 mm27 mm23.4 mm100000000000000
    M20 × 2.5 mm30 mm26 mm100000000000000
    M22 × 2.5 mm32 mm28.6 mm100000000000000
    M24 × 3 mm36 mm31.2 mm100000000000000
     
    Black-Oxide 18-8 Stainless Steel
    8-32
    11/32"1/4"50000000000000
    10-24
    3/8"1/4"50000000000000
    10-32
    3/8"1/4"50000000000000
    1/4"-20
    7/16"19/64"500000000000000
    3/8"-16
    9/16"15/32"10000000000000
    1/2"-13
    3/4"39/64"10000000000000
    1/2"-20
    3/4"39/64"10000000000000
     
    316 Stainless Steel
    M3 × 0.5 mm5.5 mm4.5 mm10000000000000
    M4 × 0.7 mm7 mm6 mm10000000000000
    M5 × 0.8 mm8 mm7.5 mm10000000000000
    M6 × 1 mm10 mm7.8 mm10000000000000
    M8 × 1.25 mm13 mm10.4 mm10000000000000
    M10 × 1.5 mm17 mm13 mm100000000000000
    M12 × 1.75 mm19 mm15.6 mm100000000000000
    M20 × 2.5 mm30 mm26 mm100000000000000
     

    Thin-Profile Flex-Top Locknuts for Heavy Vibration
    3D CAD models available

    Image of Product. Front orientation. Locknuts. Thin-Profile Flex-Top Locknuts for Heavy Vibration.
    About two-thirds the height of standard steel-insert locknuts, these fit in spaces with low clearance and offer the most secure hold of all our thin-profile locknuts. You can also use them as jam nuts by threading them against a hex nut to hold it in place. The tab on the insert stops the nut from rotating, even under extreme vibration. These locknuts are ideal for equipment with constant motion or jarring starts and stops, including conveyors, shakers, and compactors. In fact, they're so secure that they're even used to fasten components on roller coasters. These locknuts are also reusable, but their holding power decreases after the first use, so you should use a new nut for the strongest possible hold.
    Steel
    These locknuts have equivalent strength to Grade 8 and Class 10 steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Cadmium-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc-yellow-chromate plating.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    6-32
    5/16"9/64"25000000000000000
    8-32
    11/32"3/16"2500000000000000
    10-24
    3/8"3/16"2500000000000000
    10-32
    3/8"3/16"2500000000000000
    1/4"-20
    7/16"7/32"2500000000000000
    1/4"-28
    7/16"7/32"2500000000000000
    5/16"-18
    1/2"17/64"100000000000000
    5/16"-24
    1/2"17/64"100000000000000
    3/8"-16
    9/16"9/32"1000000000000000
    3/8"-24
    9/16"9/32"1000000000000000
    7/16"-20
    5/8"21/64"50000000000000
    1/2"-13
    3/4"21/64"50000000000000
    1/2"-20
    3/4"21/64"50000000000000
    5/8"-11
    15/16"13/32"10000000000000
    5/8"-18
    15/16"13/32"10000000000000
    3/4"-10
    1 1/16"27/64"10000000000000
    3/4"-16
    1 1/16"27/64"10000000000000
    7/8"-9
    1 1/4"31/64"100000000000000
    1"-8
    1 7/16"37/64"100000000000000
    1"-14
    1 7/16"37/64"10000000000000
    1 1/4"-12
    1 13/16"49/64"100000000000000
    1 1/2"-12
    2 3/16"57/64"100000000000000
     
    Steel
    6-32
    5/16"9/64"100000000000000
    8-32
    11/32"3/16"100000000000000
    10-24
    3/8"3/16"100000000000000
    10-32
    3/8"3/16"100000000000000
    1/4"-20
    7/16"7/32"100000000000000
    1/4"-28
    7/16"7/32"100000000000000
    5/16"-18
    1/2"17/64"50000000000000
    5/16"-24
    1/2"17/64"50000000000000
    3/8"-16
    9/16"9/32"50000000000000
    3/8"-24
    9/16"9/32"50000000000000
    1/2"-13
    3/4"21/64"10000000000000
    1/2"-20
    3/4"21/64"10000000000000
    5/8"-11
    15/16"13/32"10000000000000
    5/8"-18
    15/16"13/32"10000000000000
    3/4"-10
    1 1/16"27/64"10000000000000
    3/4"-16
    1 1/16"27/64"10000000000000
    1"-14
    1 7/16"37/64"10000000000000
    1 1/8"-12
    1 5/8"41/64"100000000000000
    1 1/4"-12
    1 13/16"49/64"100000000000000
    1 3/8"-12
    1 15/16"53/64"100000000000000
    1 1/2"-12
    2 3/16"57/64"100000000000000
     
    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.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    6-32
    5/16"9/64"10000000000000000
    8-32
    11/32"3/16"500000000000000
    10-24
    3/8"3/16"500000000000000
    10-32
    3/8"3/16"1000000000000000
    1/4"-20
    7/16"7/32"500000000000000
    1/4"-28
    7/16"7/32"500000000000000
    5/16"-18
    1/2"17/64"10000000000000
    5/16"-24
    1/2"17/64"10000000000000
    3/8"-16
    9/16"9/32"10000000000000
    3/8"-24
    9/16"9/32"10000000000000
    1/2"-13
    3/4"21/64"10000000000000
    1/2"-20
    3/4"21/64"100000000000000
    5/8"-18
    15/16"13/32"100000000000000
    3/4"-16
    1 1/16"27/64"100000000000000
    7/8"-14
    1 1/4"31/64"1000000000000000
     

    Heavy-Profile Flex-Top Locknuts for Heavy Vibration
    3D CAD models available

    Image of Product. Front orientation. Locknuts. Heavy-Profile Flex-Top Locknuts for Heavy Vibration.
    About 10% wider and taller than standard flex-top nuts, these handle heavier loads by distributing them over a larger area. The top section expands to grip the screw on all sides for a stronger hold than both nylon-insert and distorted-thread locknuts. As a result, they're suitable for use in equipment with constant, vigorous vibration, such as engines. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Steel
    These locknuts have equivalent strength to Grade 8 and Class 10 steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Cadmium-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc-yellow-chromate plating.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    1/4"-20
    1/2"19/64"10000000000000000
    5/16"-18
    9/16"21/64"1000000000000000
    3/8"-16
    5/8"25/64"1000000000000000
    1/2"-13
    13/16"1/2"500000000000000
    5/8"-11
    1"41/64"10000000000000
    3/4"-10
    1 1/8"49/64"10000000000000
    7/8"-9
    1 5/16"57/64"100000000000000
    1"-8
    1 1/2"1 1/64"100000000000000
     
    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.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1/4"-20
    1/2"19/64"1000000000000000
    5/16"-18
    9/16"21/64"100000000000000
    3/8"-16
    5/8"25/64"100000000000000
    7/16"-14
    3/4"29/64"100000000000000
    1/2"-13
    13/16"1/2"100000000000000
     

    Thin-Heavy-Profile Flex-Top Locknuts for Heavy Vibration
    3D CAD models available

    Image of Product. Front orientation. Locknuts. Thin-Heavy-Profile Flex-Top Locknuts for Heavy Vibration.
    About two-thirds the height of standard flex-top nuts and 10% wider, these fit in spaces with low clearance and handle heavier loads by distributing them over a larger area. Because of the thin profile, you can also use them as jam nuts by threading them against a hex nut to hold it in place. The top section expands to grip the screw on all sides for a stronger hold than both nylon-insert and distorted-thread locknuts. As a result, they're suitable for use in equipment with constant, vigorous vibration, such as engines. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Steel
    These locknuts have equivalent strength to Grade 8 and Class 10 steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Cadmium-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc-yellow-chromate plating.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    1/4"-20
    1/2"7/32"25000000000000000
    5/16"-18
    9/16"17/64"100000000000000
    3/8"-16
    5/8"9/32"1000000000000000
    7/16"-14
    3/4"21/64"10000000000000
    1/2"-13
    13/16"21/64"500000000000000
    5/8"-11
    1"13/32"10000000000000
    3/4"-10
    1 1/8"27/64"100000000000000
    7/8"-9
    1 5/16"31/64"100000000000000
    1"-8
    1 1/2"37/64"100000000000000
     

    Mil. Spec. Flex-Top Locknuts for Heavy Vibration
    3D CAD models available

    Image of Product. Front orientation. Locknuts. Mil. Spec. Flex-Top Locknuts for Heavy Vibration.
    These locknuts are manufactured and tested to strict U.S. military standards for material and construction. The top section expands to grip the screw on all sides for a stronger hold than both nylon-insert and distorted-thread locknuts. As a result, they're suitable for use in equipment with constant, vigorous vibration, such as engines. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Steel
    These locknuts have equivalent strength to Grade 8 and Class 10 steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Cadmium Yellow-Chromate-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc-yellow-chromate plating.
    Thread
    Size
    Wd.
    Ht.
    Mil.
    Spec.
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    4-40
    1/4"5/32"MS21045-045000000000000000
    6-32
    5/16"3/16"MS21045-0650000000000000
    8-32
    11/32"1/4"MS21045-08500000000000000
    10-32
    3/8"1/4"MS21045-350000000000000
    1/4"-28
    7/16"5/16"MS21045-4500000000000000
    5/16"-24
    1/2"23/64"MS21045-5500000000000000
    3/8"-24
    9/16"15/32"MS21045-6500000000000000
    7/16"-20
    11/16"15/32"MS21045-7100000000000000
    1/2"-20
    3/4"39/64"MS21045-8100000000000000
    9/16"-18
    7/8"11/16"MS21045-9100000000000000
    5/8"-18
    15/16"49/64"MS21045-10100000000000000
    3/4"-16
    1 1/16"57/64"MS21045-12100000000000000
     
    Corrosion-Resistant Stainless Steel
    Silver-Plated 18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts won't rust. The silver plating adds lubricity to help them thread on smoothly during installation.
    Thread
    Size
    Wd.
    Ht.
    Mil.
    Spec.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Silver-Plated 18-8 Stainless Steel
    4-40
    1/4"9/64"MS21046C04NASM210461000000000000000
    6-32
    5/16"11/64"MS21046C06NASM21046100000000000000
    8-32
    11/32"15/64"MS21046C08NASM2104610000000000000
    10-32
    3/8"15/64"MS21046C3NASM21046100000000000000
    1/4"-28
    7/16"9/32"MS21046C4NASM21046100000000000000
    3/8"-24
    9/16"25/64"MS21046C6NASM21046100000000000000
     
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