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    95 Products

    Hex Nut Profile

    Hex Nut Profile

    Performance

    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.
    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"-20
    		7/16"7/32"MS51967-3SAE Grade 8
    		Fed. Spec. FF-N-836
    		500000000000000
    1/4"-28
    		7/16"7/32"MS51968-3SAE Grade 8
    		Fed. Spec. FF-N-836
    		50000000000000
    5/16"-18
    		1/2"17/64"MS51967-6SAE Grade 8
    		Fed. Spec. FF-N-836
    		50000000000000
    5/16"-24
    		1/2"17/64"MS51968-6SAE Grade 8
    		Fed. Spec. FF-N-836
    		50000000000000
    3/8"-16
    		9/16"21/64"MS51967-9SAE Grade 8
    		Fed. Spec. FF-N-836
    		10000000000000
    3/8"-24
    		9/16"21/64"MS51968-9SAE Grade 8
    		Fed. Spec. FF-N-836
    		10000000000000
    7/16"-14
    		11/16"3/8"MS51967-12SAE Grade 8
    		Fed. Spec. FF-N-836
    		10000000000000
    7/16"-20
    		11/16"3/8"MS51968-12SAE Grade 8
    		Fed. Spec. FF-N-836
    		10000000000000
    1/2"-13
    		3/4"7/16"MS51967-15SAE Grade 8
    		Fed. Spec. FF-N-836
    		10000000000000
    1/2"-20
    		3/4"7/16"MS51968-15SAE Grade 8
    		Fed. Spec. FF-N-836
    		10000000000000
    9/16"-18
    		7/8"31/64"MS51968-18SAE Grade 8
    		Fed. Spec. FF-N-836
    		10000000000000
    5/8"-11
    		15/16"35/64"MS51967-21SAE Grade 8
    		Fed. Spec. FF-N-836
    		100000000000000
    5/8"-18
    		15/16"35/64"MS51968-21SAE Grade 8
    		Fed. Spec. FF-N-836
    		10000000000000
    3/4"-10
    		1 1/8"41/64"MS51967-24SAE Grade 8
    		Fed. Spec. FF-N-836
    		100000000000000
    3/4"-16
    		1 1/8"41/64"MS51968-24SAE Grade 8
    		Fed. Spec. FF-N-836
    		100000000000000
     
    Cadmium Yellow-Chromate-Plated Steel
    1/4"-20
    		7/16"7/32"MS51967-3SAE Grade 8
    		Fed. Spec. FF-N-836
    		2500000000000000
    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
     
    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.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    0-80
    		5/32"3/64"MS35650-314Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35500000000000000
    2-56
    		3/16"1/16"MS35649-224Fed. Spec. FF-N-836, Fed. Spec. QQ-P-352500000000000000
    4-40
    		1/4"3/32"MS35649-244Fed. Spec. FF-N-836, Fed. Spec. QQ-P-352500000000000000
    6-32
    		5/16"7/64"MS35649-264Fed. Spec. FF-N-836, Fed. Spec. QQ-P-352500000000000000
    8-32
    		11/32"1/8"MS35649-284Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35100000000000000
    10-24
    		3/8"1/8"MS35649-204Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35100000000000000
    10-32
    		3/8"1/8"MS35650-304Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35100000000000000
    1/4"-20
    		7/16"3/16"MS35649-2254Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35100000000000000
    1/4"-28
    		7/16"3/16"MS35650-3254Fed. Spec. FF-N-836, Fed. Spec. QQ-P-3550000000000000
    1/4"-28
    		7/16"7/32"MS51972-1Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35100000000000000
    5/16"-18
    		1/2"17/64"MS51971-2Fed. Spec. FF-N-836, Fed. Spec. QQ-P-35100000000000000
    5/16"-18
    		9/16"7/32"MS35649-2314Fed. Spec. FF-N-836, Fed. Spec. QQ-P-3550000000000000
    5/16"-24
    		1/2"17/64"MS51972-2Fed. Spec. FF-N-836, Fed. Spec. QQ-P-3550000000000000
    5/16"-24
    		9/16"7/32"MS35650-3314Fed. Spec. FF-N-836, Fed. Spec. QQ-P-3510000000000000
    3/8"-16
    		9/16"21/64"MS51971-3Fed. Spec. FF-N-836, Fed. Spec. QQ-P-3550000000000000
    3/8"-16
    		5/8"1/4"MS35649-2384Fed. Spec. FF-N-836, Fed. Spec. QQ-P-3550000000000000
    3/8"-24
    		9/16"21/64"MS51972-3Fed. Spec. FF-N-836, Fed. Spec. QQ-P-3550000000000000
    3/8"-24
    		5/8"1/4"MS35650-3384Fed. Spec. FF-N-836, Fed. Spec. QQ-P-3510000000000000
    1/2"-13
    		3/4"7/16"MS51971-5Fed. Spec. FF-N-836, Fed. Spec. QQ-P-3510000000000000
    1/2"-20
    		3/4"7/16"MS51972-5Fed. Spec. FF-N-836, Fed. Spec. QQ-P-3510000000000000
    5/8"-11
    		15/16"35/64"MS51971-7Fed. Spec. FF-N-836, Fed. Spec. QQ-P-3510000000000000
    3/4"-10
    		1 1/8"41/64"MS51971-8Fed. Spec. FF-N-836, Fed. Spec. QQ-P-3510000000000000
     
    Corrosion-Resistant Stainless Steel with Material Certificate
    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.
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Thread
    Size
    Wd.
    Ht.
    Mil.
    Spec.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1/4"-20
    		7/16"7/32"MS51971-1Fed. Spec. FF-N-836, Fed. Spec. QQ-P-351000000000000000
     

    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.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1/4"-20
    		7/16"5/32"MS35691-3Fed. Spec. FF-N-836
    		5000000000000000
    1/4"-28
    		7/16"5/32"MS35691-7Fed. Spec. FF-N-836
    		10000000000000
    5/16"-18
    		1/2"3/16"MS35691-11Fed. Spec. FF-N-836
    		500000000000000
    5/16"-24
    		1/2"3/16"MS35691-15Fed. Spec. FF-N-836
    		500000000000000
    3/8"-16
    		9/16"7/32"MS35691-19Fed. Spec. FF-N-836
    		10000000000000
    3/8"-24
    		9/16"7/32"MS35691-23Fed. Spec. FF-N-836
    		10000000000000
    7/16"-14
    		11/16"1/4"MS35691-27Fed. Spec. FF-N-836
    		10000000000000
    7/16"-20
    		11/16"1/4"MS35691-31Fed. Spec. FF-N-836
    		10000000000000
    1/2"-13
    		3/4"5/16"MS35691-35Fed. Spec. FF-N-836
    		10000000000000
    1/2"-20
    		3/4"5/16"MS35691-39Fed. Spec. FF-N-836
    		10000000000000
    5/8"-11
    		15/16"3/8"MS35691-51Fed. Spec. FF-N-836
    		100000000000000
    5/8"-18
    		15/16"3/8"MS35691-55Fed. Spec. FF-N-836
    		100000000000000
     

    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.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    0-80
    		1/8"3/64"Fed. Spec. FF-N-836, NAS671C010000000000000000
    2-56
    		5/32"1/16"Fed. Spec. FF-N-836, NAS671C21000000000000000
    4-40
    		3/16"1/16"Fed. Spec. FF-N-836, NAS671C41000000000000000
    6-32
    		1/4"3/32"Fed. Spec. FF-N-836, NAS671C61000000000000000
    8-32
    		5/16"7/64"Fed. Spec. FF-N-836, NAS671C81000000000000000
    10-32
    		11/32"1/8"Fed. Spec. FF-N-836, NAS671C10500000000000000
     
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