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    32 Products
    About Hex Nuts
    industrial info icon

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

    Left-Hand-Thread Thin-Profile Hex Nuts

    Image of Product. Front orientation. Contains Annotated, MultipleImages. Hex Nuts. Left-Hand-Thread Thin-Profile Hex Nuts.
    These nuts tighten when turned to the left. Use them with left-hand rods and screws to prevent counterclockwise-moving parts from loosening. About half the height of standard-profile nuts, these 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.
    Low-Strength Steel
    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.
    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.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Black-Oxide Steel
    10-32
    		3/8"7/64"SAE Grade 2
    		ASTM A108100000000000000
     
    Corrosion-Resistant Stainless Steel
    Highly-Corrosion-Resistant 316 Stainless Steel—Superior to 18-8 stainless steel, these nuts won't degrade when exposed to harsh weather, salt water, and most chemicals.
    Thread
    Size
    Wd.
    Ht.
    Each
    Highly-Corrosion-Resistant 316 Stainless Steel
    10-32
    		3/8"7/64"00000000000000
     
    Corrosion-Resistant Stainless Steel with Material Certificate
    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.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/8"7/64"100000000000000
     
    Brass
    Brass—Conductive and nonmagnetic, brass nuts are commonly used to secure electrical equipment, such as circuit board assemblies and mounting brackets, inside enclosures. They're also softer than most metals, so they won't damage other fastening components.
    Thread
    Size
    Wd.
    Ht.
    Each
    Brass
    10-32
    		3/8"7/64"00000000000000
     

    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.
    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
    10-32
    		11/32"1/8"Fed. Spec. FF-N-836, NAS671C105000000000000000
     

    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.
    Black-Zinc-Plated Steel—The dark zinc plating withstands occasional exposure to moisture while creating a finished look.
    Black-Corrosion-Resistant-Coated Steel—These nuts combine a finished appearance with the rust resistance of stainless steel. The coating has been tested to extreme standards, including 1,000 hours of salt spray resistance, to hold up in wet and outdoor environments. Also known as black luster.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    10-32
    		3/8"11/64"22010000000000000000
     
    Black-Zinc-Plated Steel
    10-32
    		3/8"11/64"220250000000000000
     
    Black-Corrosion-Resistant-Coated Steel
    10-32
    		3/8"11/64"22050000000000000
     
    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.
    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.
    316 Stainless Steel—Our most corrosion-resistant nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/8"11/64"2205000000000000000
     
    Black-Oxide 18-8 Stainless Steel
    10-32
    		3/8"3/16"22010000000000000000
     
    316 Stainless Steel
    10-32
    		3/8"11/64"2205000000000000000
     

    Thin-Profile Flex-Top Locknuts for Heavy Vibration

    Image of Product. Front orientation. Locknuts. Thin-Profile Flex-Top Locknuts for Heavy Vibration.
    About two-thirds the height of standard flex-top nuts, 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 top section expands to grip the screw on all sides for a stronger hold than both nylon-insert and distorted-thread locknuts. As a result, they're suitable for use in equipment with constant, vigorous vibration, such as engines. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Steel
    These locknuts have equivalent strength to Grade 8 and Class 10 steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Cadmium-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc-yellow-chromate plating.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    10-32
    		3/8"3/16"25000000000000000
     
    Steel
    10-32
    		3/8"3/16"100000000000000
     
    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.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/8"3/16"10000000000000000
     

    Low-Profile Knurled-Head Thumb Nuts

    Image of Product. Front orientation. Thumb Nuts. Low-Profile Knurled-Head Thumb Nuts.
    Image of Attribute. Front orientation. Contains Annotated. Low-Profile Knurled-Head Thumb Nuts.
    Twist these thumb nuts into spaces without a lot of clearance. They have a short, slip-resistant head, so you can grip them easily and make controlled adjustments in cramped spots. You can also use them as jam nuts by threading them against another nut to hold it in place.
    Steel
    Black-Oxide Steel—A dark, matte coating creates a finished look. These nuts offer minimal corrosion resistance, so they're best for dry environments.
    Collar
    Thread
    Size
    Dia.
    Ht.
    Head
    Dia.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Black-Oxide Steel
    10-32
    		1/2"1/16"3/4"7/32"100000000000000
     

    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.
    Passivated 18-8 Stainless Steel—With an added layer of protection, these nuts stand up to strong acids and other harsh chemicals.
    Highly-Corrosion-Resistant 316 Stainless Steel—Our most corrosion-resistant thumb nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Collar
    Thread
    Size
    Dia.
    Ht.
    Head
    Dia.
    Ht.
    Threading
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		13/32"3/16"1/2"11/32"Fully Threaded100000000000000
     
    Black-Oxide 18-8 Stainless Steel
    10-32
    		13/32"3/16"1/2"11/32"Fully Threaded10000000000000
     
    Passivated 18-8 Stainless Steel
    10-32
    		13/32"3/16"1/2"11/32"Fully Threaded10000000000000
     
    Highly-Corrosion-Resistant 316 Stainless Steel
    10-32
    		13/32"3/16"1/2"11/32"Fully Threaded100000000000000
     
    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.
    Zinc-Plated Brass—The zinc plating offers better corrosion resistance than plain brass to stand up to solvents and mild chemicals.
    Collar
    Thread
    Size
    Dia.
    Ht.
    Head
    Dia.
    Ht.
    Threading
    Pkg.
    Qty.
    Pkg.
    Brass
    10-32
    		7/16"13/64"1/2"21/64"Fully Threaded1000000000000000
     
    Zinc-Plated Brass
    10-32
    		13/32"3/16"1/2"11/32"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.
    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.
    Highly-Corrosion-Resistant 316 Stainless Steel—Our most corrosion-resistant thumb nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Collar
    Thread
    Size
    Dia.
    Ht.
    Head
    Dia.
    Ht.
    Threading
    Thread
    Dp.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/8"1/4"1/2"7/16"Fully Threaded—100000000000000
    10-32
    		3/8"1/4"1"7/16"Fully Threaded—10000000000000
    10-32
    		3/8"1/2"1/2"11/16"Partially Threaded1/4"10000000000000
    10-32
    		3/8"1/2"1"11/16"Partially Threaded1/4"10000000000000
     
    Black-Oxide 18-8 Stainless Steel
    10-32
    		3/8"1/2"1/2"11/16"Partially Threaded1/4"10000000000000
     
    Highly-Corrosion-Resistant 316 Stainless Steel
    10-32
    		3/8"1/4"1"7/16"Fully Threaded—10000000000000
     
    Plastic
    Reinforced Acetal—The best plastic for damp and wet environments, acetal won't swell or lose strength if exposed to moisture. These nuts are reinforced with an aluminum threaded insert, so they can handle more torque than other plastic nuts and won't crack during installation.
    Nylon—These nuts thread on smoothly and resist abrasion to stand up to scratches and bumps. Nylon will swell and weaken when exposed to moisture, so it's best for dry environments.
    Collar
    Thread
    Size
    Dia.
    Ht.
    Head
    Dia.
    Ht.
    Color
    Threading
    Insert
    Material
    Pkg.
    Qty.
    Pkg.
    Reinforced Acetal
    10-32
    		31/64"1/8"5/8"19/64"BlackFully ThreadedAluminum
    		1000000000000000
     
    Nylon
    10-32
    		3/8"1/4"1"7/16"BlackFully Threaded—10000000000000
     

    Hex-Head Thumb Nuts

    Image of Product. Front orientation. Contains Annotated. Thumb Nuts. Hex-Head Thumb Nuts.
    Apply extra torque to these nuts to prevent accidental loosening. Twist them on by hand, then crank with a wrench for a tight fit. 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.
    Collar
    Thread
    Size
    Dia.
    Ht.
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		13/32"3/16"1/2"11/32"100000000000000
     

    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.
    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.
    Cadmium Yellow-Chromate-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc-yellow-chromate plating.
    Thread
    Size
    Wd.
    Ht.
    Mil.
    Spec.
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    10-32
    		3/8"3/16"MS21083N3250NASM210831000000000000000
     
    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
    10-32
    		3/8"3/16"MS21083C3250NASM210835000000000000000
     
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