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    95 Products
    About Hex Nuts
    industrial info icon

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

    Hex Nut Profile

    Hex Nut Profile

    Material

    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
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    1/4"-20
    		7/16"7/32"Fed. Spec. FF-N-836, MS51967-2SAE Grade 5
    		—2594575A110000000
    1/4"-28
    		7/16"7/32"Fed. Spec. FF-N-836, MS51968-2SAE Grade 5
    		—2594575A12000000
    5/16"-18
    		1/2"17/64"Fed. Spec. FF-N-836, MS51967-5SAE Grade 5
    		—2594575A23000000
    5/16"-24
    		1/2"17/64"Fed. Spec. FF-N-836, MS51968-5SAE Grade 5
    		—2594575A24000000
    3/8"-16
    		9/16"21/64"Fed. Spec. FF-N-836, MS51967-8SAE Grade 5
    		Material Certificate
    		1094575A3500000
    3/8"-24
    		9/16"21/64"Fed. Spec. FF-N-836, MS51968-8SAE Grade 5
    		—1094575A3600000
    7/16"-14
    		11/16"3/8"Fed. Spec. FF-N-836, MS51967-11SAE Grade 5
    		—594575A7300000
    7/16"-20
    		11/16"3/8"Fed. Spec. FF-N-836, MS51968-11SAE Grade 5
    		—1094575A71000000
    1/2"-13
    		3/4"7/16"Fed. Spec. FF-N-836, MS51967-14SAE Grade 5
    		—1094575A47000000
    1/2"-20
    		3/4"7/16"Fed. Spec. FF-N-836, MS51968-14SAE Grade 5
    		—1094575A48000000
    9/16"-12
    		7/8"31/64"Fed. Spec. FF-N-836, MS51967-17SAE Grade 5
    		—594575A75000000
    5/8"-11
    		15/16"35/64"Fed. Spec. FF-N-836, MS51967-20SAE Grade 5
    		—594575A51000000
    5/8"-18
    		15/16"35/64"Fed. Spec. FF-N-836, MS51968-20SAE Grade 5
    		—594575A52000000
    3/4"-10
    		1 1/8"41/64"Fed. Spec. FF-N-836, MS51967-23SAE Grade 5
    		—194575A6300000
    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"-20
    		7/16"7/32"Fed. Spec. FF-N-836, MS51967-3SAE Grade 8
    		—594191A11100000
    1/4"-28
    		7/16"7/32"Fed. Spec. FF-N-836, MS51968-3SAE Grade 8
    		—594191A1120000
    5/16"-18
    		1/2"17/64"Fed. Spec. FF-N-836, MS51967-6SAE Grade 8
    		—594191A1130000
    5/16"-24
    		1/2"17/64"Fed. Spec. FF-N-836, MS51968-6SAE Grade 8
    		—594191A1140000
    3/8"-16
    		9/16"21/64"Fed. Spec. FF-N-836, MS51967-9SAE Grade 8
    		Material Certificate
    		194191A1150000
    3/8"-24
    		9/16"21/64"Fed. Spec. FF-N-836, MS51968-9SAE Grade 8
    		—194191A1160000
    7/16"-14
    		11/16"3/8"Fed. Spec. FF-N-836, MS51967-12SAE Grade 8
    		—194191A1170000
    7/16"-20
    		11/16"3/8"Fed. Spec. FF-N-836, MS51968-12SAE Grade 8
    		—194191A1180000
    1/2"-13
    		3/4"7/16"Fed. Spec. FF-N-836, MS51967-15SAE Grade 8
    		—194191A1190000
    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"-11
    		15/16"35/64"Fed. Spec. FF-N-836, MS51967-21SAE Grade 8
    		—194191A12200000
    5/8"-18
    		15/16"35/64"Fed. Spec. FF-N-836, MS51968-21SAE Grade 8
    		—194191A1230000
    3/4"-10
    		1 1/8"41/64"Fed. Spec. FF-N-836, MS51967-24SAE Grade 8
    		—194191A12400000
    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"-20
    		7/16"7/32"Fed. Spec. FF-N-836, MS51967-3SAE Grade 8
    		—2594191A10000000
    1/4"-28
    		7/16"7/32"Fed. Spec. FF-N-836, MS51968-3SAE Grade 8
    		—2594191A15000000
    5/16"-18
    		1/2"17/64"Fed. Spec. FF-N-836, MS51967-6SAE Grade 8
    		—2594191A20000000
    5/16"-24
    		1/2"17/64"Fed. Spec. FF-N-836, MS51968-6SAE Grade 8
    		—2594191A25000000
    3/8"-16
    		9/16"21/64"Fed. Spec. FF-N-836, MS51967-9SAE Grade 8
    		—1094191A3000000
    3/8"-24
    		9/16"21/64"Fed. Spec. FF-N-836, MS51968-9SAE Grade 8
    		—1094191A3500000
    7/16"-14
    		11/16"3/8"Fed. Spec. FF-N-836, MS51967-12SAE Grade 8
    		—594191A4000000
    7/16"-20
    		11/16"3/8"Fed. Spec. FF-N-836, MS51968-12SAE Grade 8
    		—594191A4500000
    1/2"-13
    		3/4"7/16"Fed. Spec. FF-N-836, MS51967-15SAE Grade 8
    		—594191A5000000
    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"-11
    		15/16"35/64"Fed. Spec. FF-N-836, MS51967-21SAE Grade 8
    		—594191A80000000
    5/8"-18
    		15/16"35/64"Fed. Spec. FF-N-836, MS51968-21SAE Grade 8
    		—594191A60000000
    3/4"-10
    		1 1/8"41/64"Fed. Spec. FF-N-836, MS51967-24SAE Grade 8
    		—194191A6500000
    3/4"-16
    		1 1/8"41/64"Fed. Spec. FF-N-836, MS51968-24SAE Grade 8
    		—194191A9000000
     
    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.
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    2-56
    		3/16"1/16"Fed. Spec. FF-N-836, MS35649-222—1091813A110000000
    4-40
    		1/4"3/32"Fed. Spec. FF-N-836, MS35649-242Material Certificate
    		5091813A12000000
    6-32
    		5/16"7/64"Fed. Spec. FF-N-836, MS35649-262—1091813A1300000
    8-32
    		11/32"1/8"Fed. Spec. FF-N-836, MS35649-282Material Certificate
    		5091813A14000000
    10-24
    		3/8"1/8"Fed. Spec. FF-N-836, MS35649-202—5091813A15000000
    10-32
    		3/8"1/8"Fed. Spec. FF-N-836, MS35650-302—5091813A16000000
    1/4"-20
    		7/16"3/16"Fed. Spec. FF-N-836, MS35649-2252—5091813A17000000
    5/16"-18
    		9/16"7/32"Fed. Spec. FF-N-836, MS35649-2312Material Certificate
    		2591813A18000000
    3/8"-16
    		5/8"1/4"Fed. Spec. FF-N-836, MS35649-2382—2591813A19000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Hex Nuts. Mil. Spec. Hex Nuts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Wd.
    Ht.
    Mil. Spec.
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    0-80
    		5/32"3/64"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS35650-314Material Certificate
    		591240A00100000
    2-56
    		3/16"1/16"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS35649-224Material Certificate
    		2591240A00300000
    4-40
    		1/4"3/32"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS35649-244Material Certificate
    		2591240A00500000
    6-32
    		5/16"7/64"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS35649-264Material Certificate
    		2591240A00700000
    8-32
    		11/32"1/8"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS35649-284Material Certificate
    		1091240A0090000
    10-24
    		3/8"1/8"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS35649-204—1091240A0110000
    10-32
    		3/8"1/8"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS35650-304Material Certificate
    		1091240A4110000
    1/4"-20
    		7/16"3/16"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS35649-2254Material Certificate
    		1091240A0290000
    1/4"-20
    		7/16"7/32"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS51971-1Material Certificate
    		1090762A1120000
    1/4"-28
    		7/16"3/16"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS35650-3254—591240A0780000
    1/4"-28
    		7/16"7/32"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS51972-1Material Certificate
    		1090762A1150000
    5/16"-18
    		1/2"17/64"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS51971-2Material Certificate
    		1090762A1180000
    5/16"-18
    		9/16"7/32"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS35649-2314—591240A0300000
    5/16"-24
    		1/2"17/64"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS51972-2—590762A1230000
    5/16"-24
    		9/16"7/32"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS35650-3314—191240A5110000
    3/8"-16
    		9/16"21/64"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS51971-3Material Certificate
    		590762A1270000
    3/8"-16
    		5/8"1/4"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS35649-2384Material Certificate
    		591240A03100000
    3/8"-24
    		9/16"21/64"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS51972-3—590762A1320000
    3/8"-24
    		5/8"1/4"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS35650-3384—191240A5120000
    1/2"-13
    		3/4"7/16"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS51971-5—190762A1360000
    1/2"-20
    		3/4"7/16"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS51972-5Material Certificate
    		190762A1390000
    5/8"-11
    		15/16"35/64"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS51971-7Material Certificate
    		190762A1440000
    3/4"-10
    		1 1/8"41/64"Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35, MS51971-8—190762A1470000
     

    Mil. Spec. Narrow-Profile Hex Nuts

    These nuts are manufactured and tested to strict U.S. military standards for material and construction. They are about 20% narrower to fit in tight spots where standard-profile nuts won't fit. Also known as small-pattern hex nuts.
    Corrosion-Resistant Stainless Steel
    Image of Product. Bottom orientation. Hex Nuts. Mil. Spec. Narrow-Profile Hex Nuts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Wd.
    Ht.
    Mil. Spec.
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    0-80
    		1/8"3/64"Fed. Spec. FF-N-836, NAS671C0—1091834A106000000
    2-56
    		5/32"1/16"Fed. Spec. FF-N-836, NAS671C2Material Certificate
    		1091834A1010000
    4-40
    		3/16"1/16"Fed. Spec. FF-N-836, NAS671C4Material Certificate
    		1091834A1020000
    6-32
    		1/4"3/32"Fed. Spec. FF-N-836, NAS671C6Material Certificate
    		1091834A1030000
    8-32
    		5/16"7/64"Fed. Spec. FF-N-836, NAS671C8Material Certificate
    		1091834A1040000
    10-32
    		11/32"1/8"Fed. Spec. FF-N-836, NAS671C10Material Certificate
    		591834A10500000
     

    Mil. Spec. Thin-Profile Hex Nuts

    These nuts are manufactured and tested to strict U.S. military standards for material and construction. About half the height of standard-profile nuts, they fit in spaces with low clearance. You can also use them as jam nuts by threading them against another hex nut to hold it in place.
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Hex Nuts. Mil. Spec. Thin-Profile Hex Nuts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Wd.
    Ht.
    Mil. Spec.
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1/4"-20
    		7/16"5/32"Fed. Spec. FF-N-836, MS35691-3—592101A210000000
    1/4"-28
    		7/16"5/32"Fed. Spec. FF-N-836, MS35691-7—192101A3200000
    5/16"-18
    		1/2"3/16"Fed. Spec. FF-N-836, MS35691-11Material Certificate
    		592101A43000000
    5/16"-24
    		1/2"3/16"Fed. Spec. FF-N-836, MS35691-15—592101A54000000
    3/8"-16
    		9/16"7/32"Fed. Spec. FF-N-836, MS35691-19—192101A6500000
    3/8"-24
    		9/16"7/32"Fed. Spec. FF-N-836, MS35691-23—192101A7600000
    7/16"-14
    		11/16"1/4"Fed. Spec. FF-N-836, MS35691-27Material Certificate
    		192101A10100000
    7/16"-20
    		11/16"1/4"Fed. Spec. FF-N-836, MS35691-31—192101A1020000
    1/2"-13
    		3/4"5/16"Fed. Spec. FF-N-836, MS35691-35Material Certificate
    		192101A8700000
    1/2"-20
    		3/4"5/16"Fed. Spec. FF-N-836, MS35691-39Material Certificate
    		192101A9800000
    5/8"-11
    		15/16"3/8"Fed. Spec. FF-N-836, MS35691-51—192101A10300000
    5/8"-18
    		15/16"3/8"Fed. Spec. FF-N-836, MS35691-55—192101A10400000
     
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