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    22 Products
    About Hex Nuts
    industrial info icon

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

    Thin-Profile Hex Nuts

    Image of Product. Front orientation. Hex Nuts. Thin-Profile Hex Nuts.
    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.
    Medium-Strength Steel
    These Grade 5 or Class 04 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.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    5/16"-18
    1/2"3/16"SAE Grade 5
    ASME B18.2.210000000000000000
     
    Steel
    5/16"-18
    1/2"3/16"SAE Grade 5
    ASME B18.2.2500000000000000
     
    High-Strength Steel
    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.
    Zinc-Yellow-Chromate-Plated Steel—With a more durable finish than clear zinc plating, these nuts are suitable for most wet and outdoor environments. However, they won't hold up to the harsh chemicals that stainless steel can.
    Zinc-Flake-Coated Steel—The most durable zinc coating, zinc flake is a multilayer finish that resists wear for long-term rust protection. Similar to zinc yellow-chromate, it won't hold up to harsh chemicals like stainless steel can.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Yellow-Chromate-Plated Steel
    5/16"-18
    1/2"3/16"SAE Grade 8
    ASME B18.2.250000000000000000
     
    Zinc-Flake-Coated Steel
    5/16"-18
    1/2"3/16"SAE Grade 8
    ASME B18.2.22500000000000000
     
    Steel
    5/16"-18
    1/2"3/16"SAE Grade 8
    ASME B18.2.25000000000000000
     
    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.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    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.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    5/16"-18
    1/2"3/16"SAE Grade 2
    10000000000000000
     
    Black-Oxide Steel
    5/16"-18
    1/2"3/16"10000000000000000
     
    Steel
    5/16"-18
    1/2"3/16"SAE Grade 2
    1000000000000000
     
    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—Superior to 18-8 stainless steel, these nuts won't degrade when exposed to harsh weather, salt water, and most chemicals.
    Highly Corrosion-Resistant Black-Oxide 316 Stainless Steel—Combines a finished appearance with the rust resistance of 316 stainless steel. Even if the coating wears off, these nuts will hold up in just about any environment, including salt water and most chemicals.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    5/16"-18
    1/2"3/16"10000000000000000
     
    Black-Oxide 18-8 Stainless Steel
    5/16"-18
    1/2"3/16"250000000000000
     
    Highly Corrosion-Resistant 316 Stainless Steel
    5/16"-18
    1/2"3/16"250000000000000
     
    Highly Corrosion-Resistant Black-Oxide 316 Stainless Steel
    5/16"-18
    1/2"3/16"250000000000000
     
    Lightweight Aluminum
    6061 Aluminum—One-third the weight of steel, these nuts are commonly used in robotics, automation, and other applications that have weight limitations. They're an alternative to stainless steel for rust resistance but are not as strong.
    Thread
    Size
    Wd.
    Ht.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    6061 Aluminum
    5/16"-18
    1/2"3/16"ASME B18.2.25000000000000000
     
    Lightweight Corrosion-Resistant Titanium
    Grade 2 Titanium—The best of both worlds, these nuts are lightweight like aluminum and as corrosion resistant as 316 stainless steel. Because Grade 2 titanium is 99% pure, it's even more corrosion resistant than other common titanium grades, such as Grades 5 and 9. These nuts are ideal for use in chemical-processing and water-treatment facilities since they stand up to strong acids and other harsh chemicals.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Grade 2 Titanium
    5/16"-18
    1/2"3/16"100000000000000
     
    Bronze
    Silicon Bronze—More resistant to salt water than brass, these nuts are a good choice for marine environments. They are also stronger than brass and more resistant to abrasion and wear. Choose them for machinery with rotating parts or other applications where nearby components may rub against the nut.
    Thread
    Size
    Wd.
    Ht.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Silicon Bronze
    5/16"-18
    1/2"3/16"ASME B18.2.225000000000000000
     
    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.
    Pkg.
    Qty.
    Pkg.
    Brass
    5/16"-18
    1/2"3/16"2500000000000000
     

    Mil. Spec. Thin-Profile Hex Nuts

    Image of Product. Front orientation. Hex Nuts. 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
    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
    5/16"-18
    1/2"3/16"MS35691-11Fed. Spec. FF-N-836
    5000000000000000
     

    Jam Nuts for Turnbuckles

    Tighten these nuts against the turnbuckle body to prevent the end fitting from unscrewing.
    For Steel Turnbuckles
    Image of Product. Front orientation. Turnbuckles. Jam Nuts for Turnbuckles.
    Left- and Right-Hand
    Thread Direction
    Thread
    Size
    Wd.
    Ht.
    Includes
    Each
    Grade 2 Steel
    5/16"-18
    1/2"3/16"One Left-Hand Threaded Jam Nut, One Right-Hand Threaded Jam Nut0000000000000
     
    For Galvanized Steel Turnbuckles
    Image of Product. Front orientation. Turnbuckles. Jam Nuts for Turnbuckles.
    Left- and Right-Hand
    Thread Direction
    Thread
    Size
    Wd.
    Ht.
    Includes
    Each
    Grade 2 Galvanized Steel
    5/16"-18
    1/2"3/16"One Left-Hand Threaded Jam Nut, One Right-Hand Threaded Jam Nut0000000000000
     

    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.
    Medium-Strength Steel
    These Grade 5 or Class 04 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.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    5/16"-18
    1/2"3/16"SAE Grade 5
    50000000000000000
     
    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.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Steel
    5/16"-18
    1/2"3/16"SAE Grade 2
    5000000000000000
     
    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.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    5/16"-18
    1/2"3/16"500000000000000
     
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