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    102 Products

    Top-Lock Distorted-Thread Locknuts

    Image of Product. Front orientation. Locknuts. 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.
    Extreme-Strength Steel
    About 20% stronger than high-strength steel locknuts, these Grade 9 nuts are the strongest we offer. Make sure to use them with Grade 9 screws to avoid stripped threads during installation.
    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.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    1/4"-20
    7/16"19/64"SAE Grade 9
    25000000000000000
    5/16"-18
    1/2"21/64"SAE Grade 9
    2500000000000000
    3/8"-16
    9/16"25/64"SAE Grade 9
    100000000000000
    7/16"-14
    11/16"29/64"SAE Grade 9
    100000000000000
    1/2"-13
    3/4"17/32"SAE Grade 9
    50000000000000
    5/8"-11
    15/16"11/16"SAE Grade 9
    10000000000000
    3/4"-10
    1 1/8"25/32"SAE Grade 9
    10000000000000
     
    High-Strength Steel
    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.
    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.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    1/4"-20
    7/16"7/32"ASTM Grade C
    100000000000000000
    1/4"-28
    7/16"7/32"ASTM Grade C
    10000000000000000
    5/16"-18
    1/2"17/64"ASTM Grade C
    10000000000000000
    5/16"-24
    1/2"17/64"ASTM Grade C
    10000000000000000
    3/8"-16
    9/16"21/64"ASTM Grade C
    10000000000000000
    3/8"-24
    9/16"21/64"ASTM Grade C
    500000000000000
    7/16"-14
    11/16"3/8"ASTM Grade C
    5000000000000000
    7/16"-20
    11/16"3/8"ASTM Grade C
    5000000000000000
    1/2"-13
    3/4"7/16"ASTM Grade C
    5000000000000000
    1/2"-20
    3/4"7/16"ASTM Grade C
    5000000000000000
    9/16"-12
    7/8"31/64"ASTM Grade C
    2500000000000000
    9/16"-18
    7/8"31/64"ASTM Grade C
    2500000000000000
    5/8"-11
    15/16"35/64"ASTM Grade C
    2500000000000000
    5/8"-18
    15/16"35/64"ASTM Grade C
    2500000000000000
    3/4"-10
    1 1/8"41/64"ASTM Grade C
    1000000000000000
    3/4"-16
    1 1/8"41/64"ASTM Grade C
    1000000000000000
    7/8"-9
    1 5/16"3/4"ASTM Grade C
    1000000000000000
    7/8"-14
    1 5/16"3/4"ASTM Grade C
    50000000000000
    1"-8
    1 1/2"55/64"ASTM Grade C
    500000000000000
    1"-14
    1 1/2"55/64"ASTM Grade C
    500000000000000
     

    Flex-Top Locknuts for Heavy Vibration

    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.
    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
    4-40
    1/4"5/32"10000000000000000
    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
     

    Thin-Profile Flex-Top Locknuts for Heavy Vibration

    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.
    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"10000000000000
    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
     

    Heavy-Profile Flex-Top Locknuts for Heavy Vibration

    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
     

    Thin-Heavy-Profile Flex-Top Locknuts for Heavy Vibration

    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. Distorted-Thread Flange Nuts

    Image of Product. Front orientation. Flange Nuts. Mil. Spec. Distorted-Thread Flange Nuts.
    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
    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.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Mil.
    Spec.
    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
     
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