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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
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    1/4"-28
    		7/16"7/32"Fed. Spec. FF-N-836, MS51968-2SAE Grade 5
    		2594575A120000000
    5/16"-24
    		1/2"17/64"Fed. Spec. FF-N-836, MS51968-5SAE Grade 5
    		2594575A24000000
    3/8"-24
    		9/16"21/64"Fed. Spec. FF-N-836, MS51968-8SAE Grade 5
    		1094575A3600000
    7/16"-20
    		11/16"3/8"Fed. Spec. FF-N-836, MS51968-11SAE Grade 5
    		1094575A71000000
    1/2"-20
    		3/4"7/16"Fed. Spec. FF-N-836, MS51968-14SAE Grade 5
    		1094575A48000000
    5/8"-18
    		15/16"35/64"Fed. Spec. FF-N-836, MS51968-20SAE Grade 5
    		594575A52000000
    3/4"-16
    		1 1/8"41/64"Fed. Spec. FF-N-836, MS51968-23SAE Grade 5
    		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.
    Material Certificate—Nuts include a report with a traceable lot number and a description of their chemical and physical properties.
    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
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Black-Oxide Steel
    1/4"-28
    		7/16"7/32"Fed. Spec. FF-N-836, MS51968-3SAE Grade 8
    		—594191A11200000
    5/16"-24
    		1/2"17/64"Fed. Spec. FF-N-836, MS51968-6SAE Grade 8
    		—594191A1140000
    3/8"-24
    		9/16"21/64"Fed. Spec. FF-N-836, MS51968-9SAE Grade 8
    		—194191A1160000
    7/16"-20
    		11/16"3/8"Fed. Spec. FF-N-836, MS51968-12SAE Grade 8
    		—194191A1180000
    1/2"-20
    		3/4"7/16"Fed. Spec. FF-N-836, MS51968-15SAE Grade 8
    		—194191A1200000
    9/16"-18
    		7/8"31/64"Fed. Spec. FF-N-836, MS51968-18SAE Grade 8
    		—194191A1210000
    5/8"-18
    		15/16"35/64"Fed. Spec. FF-N-836, MS51968-21SAE Grade 8
    		—194191A1230000
    3/4"-16
    		1 1/8"41/64"Fed. Spec. FF-N-836, MS51968-24SAE Grade 8
    		Material Certificate
    		194191A12500000
     
    Cadmium Yellow-Chromate-Plated Steel
    1/4"-28
    		7/16"7/32"Fed. Spec. FF-N-836, MS51968-3SAE Grade 8
    		—2594191A15000000
    5/16"-24
    		1/2"17/64"Fed. Spec. FF-N-836, MS51968-6SAE Grade 8
    		—2594191A25000000
    3/8"-24
    		9/16"21/64"Fed. Spec. FF-N-836, MS51968-9SAE Grade 8
    		—1094191A3500000
    7/16"-20
    		11/16"3/8"Fed. Spec. FF-N-836, MS51968-12SAE Grade 8
    		—594191A4500000
    1/2"-20
    		3/4"7/16"Fed. Spec. FF-N-836, MS51968-15SAE Grade 8
    		—594191A5500000
    9/16"-18
    		7/8"31/64"Fed. Spec. FF-N-836, MS51968-18SAE Grade 8
    		—594191A7500000
    5/8"-18
    		15/16"35/64"Fed. Spec. FF-N-836, MS51968-21SAE Grade 8
    		—594191A60000000
    3/4"-16
    		1 1/8"41/64"Fed. Spec. FF-N-836, MS51968-24SAE Grade 8
    		—194191A9000000
     
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