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    82 Products
    About Hex Nuts
    industrial info icon

    Choose a hex nut with the right profile, material, and strength for your application.

    Mil. Spec. Hex Nuts

    These nuts are manufactured and tested to strict U.S. military standards for material and construction.
    Medium-Strength Steel
    Image of Product. Front orientation. Hex Nuts. Mil. Spec. Hex Nuts.
    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.
    Cadmium Yellow-Chromate-Plated Steel— The plating creates a barrier against rust, so these nuts are suitable for most wet and outdoor environments. They also thread on smoothly without sticking.
    Thread
    Size
    Wd.
    Ht.
    Mil.
    Spec.
    Fastener Strength
    Grade/Class
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    1/4"-20
    7/16"7/32"MS51967-2SAE Grade 5
    Fed. Spec. FF-N-836
    25000000000000000
    1/4"-28
    7/16"7/32"MS51968-2SAE Grade 5
    Fed. Spec. FF-N-836
    2500000000000000
    5/16"-18
    1/2"17/64"MS51967-5SAE Grade 5
    Fed. Spec. FF-N-836
    2500000000000000
    5/16"-24
    1/2"17/64"MS51968-5SAE Grade 5
    Fed. Spec. FF-N-836
    2500000000000000
    3/8"-16
    9/16"21/64"MS51967-8SAE Grade 5
    Fed. Spec. FF-N-836
    100000000000000
    3/8"-24
    9/16"21/64"MS51968-8SAE Grade 5
    Fed. Spec. FF-N-836
    100000000000000
    7/16"-14
    11/16"3/8"MS51967-11SAE Grade 5
    Fed. Spec. FF-N-836
    50000000000000
    7/16"-20
    11/16"3/8"MS51968-11SAE Grade 5
    Fed. Spec. FF-N-836
    1000000000000000
    1/2"-13
    3/4"7/16"MS51967-14SAE Grade 5
    Fed. Spec. FF-N-836
    1000000000000000
    1/2"-20
    3/4"7/16"MS51968-14SAE Grade 5
    Fed. Spec. FF-N-836
    1000000000000000
    9/16"-12
    7/8"31/64"MS51967-17SAE Grade 5
    Fed. Spec. FF-N-836
    500000000000000
    5/8"-11
    15/16"35/64"MS51967-20SAE Grade 5
    Fed. Spec. FF-N-836
    500000000000000
    5/8"-18
    15/16"35/64"MS51968-20SAE Grade 5
    Fed. Spec. FF-N-836
    500000000000000
    3/4"-10
    1 1/8"41/64"MS51967-23SAE Grade 5
    Fed. Spec. FF-N-836
    10000000000000
    3/4"-16
    1 1/8"41/64"MS51968-23SAE Grade 5
    Fed. Spec. FF-N-836
    500000000000000
     
    High-Strength Steel
    Image of Product. Front orientation. Hex Nuts. Mil. Spec. Hex Nuts.
    Rated Grade 8, Grade C, or Class 10, these nuts are about 25% stronger than medium-strength steel nuts. They are commonly used to fasten components in valves, pumps, motors, and other high-stress applications. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Cadmium Yellow-Chromate-Plated Steel— The plating creates a barrier against rust, so these nuts are suitable for most wet and outdoor environments. They also thread on smoothly without sticking.
    Thread
    Size
    Wd.
    Ht.
    Mil.
    Spec.
    Fastener Strength
    Grade/Class
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    1/4"-20
    7/16"7/32"MS51967-3SAE Grade 8
    Fed. Spec. FF-N-836
    25000000000000000
    1/4"-28
    7/16"7/32"MS51968-3SAE Grade 8
    Fed. Spec. FF-N-836
    2500000000000000
    5/16"-18
    1/2"17/64"MS51967-6SAE Grade 8
    Fed. Spec. FF-N-836
    2500000000000000
    5/16"-24
    1/2"17/64"MS51968-6SAE Grade 8
    Fed. Spec. FF-N-836
    2500000000000000
    3/8"-16
    9/16"21/64"MS51967-9SAE Grade 8
    Fed. Spec. FF-N-836
    100000000000000
    3/8"-24
    9/16"21/64"MS51968-9SAE Grade 8
    Fed. Spec. FF-N-836
    100000000000000
    7/16"-14
    11/16"3/8"MS51967-12SAE Grade 8
    Fed. Spec. FF-N-836
    50000000000000
    7/16"-20
    11/16"3/8"MS51968-12SAE Grade 8
    Fed. Spec. FF-N-836
    50000000000000
    1/2"-13
    3/4"7/16"MS51967-15SAE Grade 8
    Fed. Spec. FF-N-836
    50000000000000
    1/2"-20
    3/4"7/16"MS51968-15SAE Grade 8
    Fed. Spec. FF-N-836
    50000000000000
    9/16"-18
    7/8"31/64"MS51968-18SAE Grade 8
    Fed. Spec. FF-N-836
    50000000000000
    5/8"-11
    15/16"35/64"MS51967-21SAE Grade 8
    Fed. Spec. FF-N-836
    500000000000000
    5/8"-18
    15/16"35/64"MS51968-21SAE Grade 8
    Fed. Spec. FF-N-836
    500000000000000
    3/4"-10
    1 1/8"41/64"MS51967-24SAE Grade 8
    Fed. Spec. FF-N-836
    10000000000000
    3/4"-16
    1 1/8"41/64"MS51968-24SAE Grade 8
    Fed. Spec. FF-N-836
    10000000000000
     
    Low-Strength Steel
    Image of Product. Front orientation. Hex Nuts. Mil. Spec. Hex Nuts.
    Rated Grade 2, Class 6, or lower, these nuts are about half as strong as medium-strength nuts. They are suitable for light duty fastening applications, such as securing access panels. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Cadmium Yellow-Chromate-Plated Steel— The plating creates a barrier against rust, so these nuts are suitable for most wet and outdoor environments. They also thread on smoothly without sticking.
    Thread
    Size
    Wd.
    Ht.
    Mil. Spec.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    2-56
    3/16"1/16"MS35649-222Fed. Spec. FF-N-836
    10000000000000000
    4-40
    1/4"3/32"MS35649-242Fed. Spec. FF-N-836
    5000000000000000
    6-32
    5/16"7/64"MS35649-262Fed. Spec. FF-N-836
    100000000000000
    8-32
    11/32"1/8"MS35649-282Fed. Spec. FF-N-836
    5000000000000000
    10-24
    3/8"1/8"MS35649-202Fed. Spec. FF-N-836
    5000000000000000
    10-32
    3/8"1/8"MS35650-302Fed. Spec. FF-N-836
    5000000000000000
    1/4"-20
    7/16"3/16"MS35649-2252Fed. Spec. FF-N-836
    5000000000000000
    5/16"-18
    9/16"7/32"MS35649-2312Fed. Spec. FF-N-836
    2500000000000000
    3/8"-16
    5/8"1/4"MS35649-2382Fed. Spec. FF-N-836
    2500000000000000
     

    Hex Nuts

    Image of Product. Front orientation. Hex Nuts. Hex Nuts.
    The most commonly used hex nuts, these are suitable for fastening most machinery and equipment.
    Extreme-Strength Steel
    These nuts are about 20% stronger than high-strength steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Cadmium Yellow-Chromate-Plated Steel— The plating creates a barrier against rust, so these nuts are suitable for most wet and outdoor environments. They also thread on smoothly without sticking.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    1/4"-20
    7/16"17/64"SAE Grade 9
    50000000000000000
    1/4"-28
    7/16"17/64"SAE Grade 9
    5000000000000000
    5/16"-18
    1/2"5/16"SAE Grade 9
    250000000000000
    5/16"-24
    1/2"5/16"SAE Grade 9
    250000000000000
    3/8"-16
    9/16"25/64"SAE Grade 9
    2500000000000000
    3/8"-24
    9/16"25/64"SAE Grade 9
    2500000000000000
    7/16"-14
    11/16"7/16"SAE Grade 9
    100000000000000
    7/16"-20
    11/16"7/16"SAE Grade 9
    100000000000000
    1/2"-13
    3/4"17/32"SAE Grade 9
    100000000000000
    1/2"-20
    3/4"17/32"SAE Grade 9
    100000000000000
    5/8"-11
    15/16"11/16"SAE Grade 9
    50000000000000
    5/8"-18
    15/16"11/16"SAE Grade 9
    50000000000000
    3/4"-10
    1 1/8"25/32"SAE Grade 9
    10000000000000
    3/4"-16
    1 1/8"25/32"SAE Grade 9
    10000000000000
    7/8"-9
    1 5/16"55/64"SAE Grade 9
    10000000000000
    7/8"-14
    1 5/16"55/64"SAE Grade 9
    10000000000000
    1"-8
    1 1/2"1"SAE Grade 9
    100000000000000
    1"-14
    1 1/2"1"SAE Grade 9
    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 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.
    Spec.
    Pkg.
    Qty.
    Pkg.
    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
     

    Mil. Spec. Nylon-Insert Locknuts

    Image of Product. Front orientation. Locknuts. Mil. Spec. Nylon-Insert Locknuts.
    These locknuts are manufactured and tested to strict U.S. military standards for material and construction. 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.
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    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.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    4-40
    1/4"5/32"MS21044-N042501000000000000000
    6-32
    5/16"3/16"MS21044-N06250100000000000000
    8-32
    11/32"9/32"MS21044-N08250100000000000000
    10-32
    3/8"9/32"MS21044-N3250100000000000000
    1/4"-28
    7/16"23/64"MS21044-N4250100000000000000
    5/16"-24
    1/2"23/64"MS21044-N525050000000000000
    3/8"-24
    9/16"15/32"MS21044-N6250500000000000000
    1/2"-20
    3/4"19/32"MS21044-N825050000000000000
    5/8"-18
    15/16"3/4"MS21044-N1025010000000000000
     

    Mil. Spec. Thin-Profile Nylon-Insert Locknuts

    Image of Product. Front orientation. Locknuts. Mil. Spec. Thin-Profile Nylon-Insert Locknuts.
    These locknuts are manufactured and tested to strict U.S. military standards for material and construction. They are about half the height of standard-profile locknuts to fit in spaces with low clearance. You can also use them as jam nuts by threading them against a hex nut to hold it in place. 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.
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    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.
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    4-40
    1/4"1/8"MS21083N04250NASM2108310000000000000000
    6-32
    5/16"9/64"MS21083N06250NASM210831000000000000000
    8-32
    11/32"3/16"MS21083N08250NASM21083100000000000000
    10-32
    3/8"3/16"MS21083N3250NASM21083100000000000000
    1/4"-28
    7/16"7/32"MS21083N4250NASM21083100000000000000
    1/2"-20
    3/4"5/16"MS21083N8250NASM2108310000000000000
     

    Press-Fit Locknuts for Sheet Metal

    Image of Product. Bottom orientation. Press-Fit Nuts.  Press-Fit Locknuts for Sheet Metal.
    Image of Product. Bottom orientation. Press-Fit Nuts.  Press-Fit Locknuts for Sheet Metal.
    The nylon insert inside these nuts grips screws so they won't back out or loosen. Use them to keep thin parts fastened on engines and other vibrating machinery.
    Cadmium Yellow-Chromate-Plated Steel—Thread fasteners on these nuts smoothly without sticking. The plating also creates a stronger barrier against rust than zinc.
    Thread
    Size
    Drill Bit
    Size
    For Min.
    Panel Thk.
    For Maximum Panel
    Hardness
    Head
    Ht.
    Flange
    Dia.
    Pkg.
    Qty.
    Pkg.
    Nylon-Insert Locking
     
    Cadmium Yellow-Chromate-Plated Steel
    6-32
    3/16"
    0.05"Brinell 205, Rockwell B950.13"0.28"1000000000000000
    10-32
    1/4"
    0.05"Brinell 205, Rockwell B950.18"0.34"100000000000000
     
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