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    8 Products
    About Hex Nuts
    industrial info icon

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

    Mil. Spec. Narrow-Profile Hex Nuts

    Image of Product. Bottom orientation. Hex Nuts. 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.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Corrosion-Resistant Stainless Steel
    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
    2-56
    		5/32"1/16"Fed. Spec. FF-N-836, NAS671C21000000000000000
     

    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.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Wd.
    Ht.
    Mil.
    Spec.
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    2-56
    		1/4"7/64"MS21083C02250NASM210835000000000000000
     

    Thin-Profile Nylon-Insert Locknuts

    Image of Product. Front orientation. Locknuts. Thin-Profile Nylon-Insert Locknuts.
    About half the height of standard-profile locknuts, these 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.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    2-56
    		1/4"7/64"220100000000000000000
     

    Flanged Knurled-Head Thumb Nuts

    Image of Attribute. Front orientation. Contains Annotated. Thumb Nuts. Flanged Knurled-Head Thumb Nuts.
    The slip-resistant head is easy to grip, while the flange distributes pressure evenly across the mounting surface without the need for a separate washer. These nuts are often used to secure screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts.
    Corrosion-Resistant Stainless Steel
    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.
    Black-Oxide 18-8 Stainless Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They resist rust in wet and outdoor environments, but won't hold up to the harsh chemicals that 316 stainless steel can.
    Collar
    Thread
    Size
    Dia.
    Ht.
    Head
    Dia.
    Ht.
    Threading
    Each
    18-8 Stainless Steel
    2-56
    		3/16"1/8"1/4"1/4"Fully Threaded00000000000000
     
    Black-Oxide 18-8 Stainless Steel
    2-56
    		3/16"1/8"1/4"1/4"Fully Threaded0000000000000
     
    Brass
    Brass—With a warm, polished look, these nuts are often chosen for their appearance. Similar to 18-8 stainless steel, brass is corrosion resistant enough to stand up to wet environments. It is also softer than other metals, so it's easier to thread together.
    Collar
    Thread
    Size
    Dia.
    Ht.
    Head
    Dia.
    Ht.
    Threading
    Pkg.
    Qty.
    Pkg.
    Brass
    2-56
    		3/16"1/8"1/4"1/4"Fully Threaded100000000000000
     

    Knurled-Head Thumb Nuts

    Image of Attribute. Front orientation. Contains Annotated. Thumb Nuts. Knurled-Head Thumb Nuts.
    Get a good grip on these nuts, even with oily fingers. They have a raised, slip-resistant head, so you can tighten them by hand and make controlled adjustments. Knurled-head nuts have a smaller profile than wing nuts, so they fit in tighter spots.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Corrosion-Resistant Stainless Steel
    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.
    Black-Oxide 18-8 Stainless Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They resist rust in wet and outdoor environments, but won't hold up to the harsh chemicals that 316 stainless steel can.
    Collar
    Thread
    Size
    Dia.
    Ht.
    Head
    Dia.
    Ht.
    Threading
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    2-56
    		7/32"3/16"3/8"1/4"Fully Threaded100000000000000
     
    Black-Oxide 18-8 Stainless Steel
    2-56
    		7/32"3/16"3/8"1/4"Fully Threaded10000000000000
     
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