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    23 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"-28
    7/16"7/32"MS51968-2SAE Grade 5
    Fed. Spec. FF-N-836
    2594575A120000000
    5/16"-24
    1/2"17/64"MS51968-5SAE Grade 5
    Fed. Spec. FF-N-836
    2594575A24000000
    3/8"-24
    9/16"21/64"MS51968-8SAE Grade 5
    Fed. Spec. FF-N-836
    1094575A3600000
    7/16"-20
    11/16"3/8"MS51968-11SAE Grade 5
    Fed. Spec. FF-N-836
    1094575A71000000
    1/2"-20
    3/4"7/16"MS51968-14SAE Grade 5
    Fed. Spec. FF-N-836
    1094575A48000000
    5/8"-18
    15/16"35/64"MS51968-20SAE Grade 5
    Fed. Spec. FF-N-836
    594575A52000000
    3/4"-16
    1 1/8"41/64"MS51968-23SAE Grade 5
    Fed. Spec. FF-N-836
    594575A64000000
     
    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.
    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 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.
    Black-Oxide Steel
    1/4"-28
    7/16"7/32"MS51968-3SAE Grade 8
    Fed. Spec. FF-N-836
    594191A11200000
    5/16"-24
    1/2"17/64"MS51968-6SAE Grade 8
    Fed. Spec. FF-N-836
    594191A1140000
    3/8"-24
    9/16"21/64"MS51968-9SAE Grade 8
    Fed. Spec. FF-N-836
    194191A1160000
    7/16"-20
    11/16"3/8"MS51968-12SAE Grade 8
    Fed. Spec. FF-N-836
    194191A1180000
    1/2"-20
    3/4"7/16"MS51968-15SAE Grade 8
    Fed. Spec. FF-N-836
    194191A1200000
    9/16"-18
    7/8"31/64"MS51968-18SAE Grade 8
    Fed. Spec. FF-N-836
    194191A1210000
    5/8"-18
    15/16"35/64"MS51968-21SAE Grade 8
    Fed. Spec. FF-N-836
    194191A1230000
    3/4"-16
    1 1/8"41/64"MS51968-24SAE Grade 8
    Fed. Spec. FF-N-836
    194191A12500000
     
    Cadmium Yellow-Chromate-Plated Steel
    1/4"-28
    7/16"7/32"MS51968-3SAE Grade 8
    Fed. Spec. FF-N-836
    2594191A15000000
    5/16"-24
    1/2"17/64"MS51968-6SAE Grade 8
    Fed. Spec. FF-N-836
    2594191A25000000
    3/8"-24
    9/16"21/64"MS51968-9SAE Grade 8
    Fed. Spec. FF-N-836
    1094191A3500000
    7/16"-20
    11/16"3/8"MS51968-12SAE Grade 8
    Fed. Spec. FF-N-836
    594191A4500000
    1/2"-20
    3/4"7/16"MS51968-15SAE Grade 8
    Fed. Spec. FF-N-836
    594191A5500000
    9/16"-18
    7/8"31/64"MS51968-18SAE Grade 8
    Fed. Spec. FF-N-836
    594191A7500000
    5/8"-18
    15/16"35/64"MS51968-21SAE Grade 8
    Fed. Spec. FF-N-836
    594191A60000000
    3/4"-16
    1 1/8"41/64"MS51968-24SAE Grade 8
    Fed. Spec. FF-N-836
    194191A9000000
     
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