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    25 Products
    About Hex Nuts
    industrial info icon

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

    Hex Nuts

    The most commonly used hex nuts, these are suitable for fastening most machinery and equipment.
    Medium-Strength Steel
    Image of Product. Front orientation. Hex Nuts. Hex Nuts.
    Image of Specification. Front orientation. Hex Nuts. 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.
    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
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1 3/8"-6
    		2 1/16"1 11/64"SAE Grade 5
    		ASME B18.2.2195462A56200000
     
    Black-Oxide Steel
    1 3/8"-6
    		2 1/16"1 3/16"SAE Grade 5
    		ASME B18.2.2195479A2220000
     
    Steel
    1 3/8"-6
    		2 1/16"1 11/64"SAE Grade 5
    		ASME B18.2.2195505A6240000
     
    High-Strength Steel
    Image of Product. Front orientation. Hex Nuts. Hex Nuts.
    Image of Specification. Front orientation. Hex Nuts. 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.
    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.
    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.
    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.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Zinc-Yellow-Chromate-Plated Steel
    1 3/8"-6
    		2 1/16"1 11/64"SAE Grade 8
    		—194895A042000000
     
    Black-Oxide Steel
    1 3/8"-6
    		2 1/16"1 11/64"SAE Grade 8
    		Material Certificate
    		194895A62800000
     
    Steel
    1 3/8"-6
    		2 1/16"1 11/64"SAE Grade 8
    		—190499A0420000
     
    Zinc-Flake-Coated Steel
    1 3/8"-6
    		2 1/16"1 11/64"SAE Grade 8
    		—193827A2920000
     
    Low-Strength Steel
    Image of Product. Front orientation. Hex Nuts. Hex Nuts.
    Image of Specification. Front orientation. Hex Nuts. 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.
    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
    1 3/8"-6
    		2 1/16"1 11/64"SAE Grade 2
    		ASME B18.2.2190473A04200000
     
    Steel
    1 3/8"-6
    		2 1/16"1 11/64"SAE Grade 2
    		ASME B18.2.2190490A4420000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Hex Nuts. Hex Nuts.
    Image of Specification. Front orientation. Hex Nuts. 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.
    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.
    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.
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1 3/8"-6
    		2 1/16"1 11/64"Material Certificate
    		191845A04200000
     
    Highly Corrosion-Resistant 316 Stainless Steel
    1 3/8"-6
    		2 1/16"1 11/64"Material Certificate
    		194804A1690000
     

    Heavy-Profile Hex Nuts

    About 10% wider and taller than standard-profile hex nuts, these handle heavier loads by distributing them over a larger area.
    Medium-Strength Steel
    Image of Product. Front orientation. Hex Nuts. Heavy-Profile 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.
    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
    1 3/8"-6
    		2 3/16"1 11/32"SAE Grade 5
    		195045A04100000
     
    Extreme-Strength Steel
    Image of Product. Front orientation. Hex Nuts. Heavy-Profile Hex Nuts.
    These nuts are about 20% stronger than high-strength steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Hot-Dipped Galvanized Steel—Combines the strength of steel with the rust resistance of stainless steel. These nuts are an economical alternative to 18-8 stainless steel in wet and outdoor environments, but they won't hold up to salt water and chemicals. The galvanized finish is thicker than other types of coatings, so the threads may be more likely to stick during installation. Use with other hot-dipped galvanized fasteners.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Specs. Met
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Hot-Dipped Galvanized Steel
    1 3/8"-6
    		2 3/16"1 11/32"ASTM Grade 2H
    		ASTM A194
    		—195025A43700000
     
    Steel
    1 3/8"-6
    		2 3/16"1 11/32"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194Material Certificate
    		190521A2900000
     
    Low-Strength Steel
    Image of Product. Front orientation. Hex Nuts. Heavy-Profile 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.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Steel
    1 3/8"-6
    		2 3/16"1 11/32"ASME B18.2.2190498A04200000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Hex Nuts. Heavy-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.
    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.
    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.
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1 3/8"-6
    		2 3/16"1 11/32"Material Certificate
    		191849A042000000
     
    Highly Corrosion-Resistant 316 Stainless Steel
    1 3/8"-6
    		2 3/16"1 11/32"Material Certificate
    		191850A04200000
     
    Brass
    Image of Product. Front orientation. Hex Nuts. Heavy-Profile Hex Nuts.
    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.
    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.
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Brass
    1 3/8"-6
    		2 3/16"1 11/32"Material Certificate
    		192680A055000000
     

    Nylon-Insert Locknuts

    Image of Product. Front orientation. Locknuts. Nylon-Insert Locknuts.
    Versatile yet economical, these are the most commonly used locknuts. 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.
    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.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1 3/8"-6
    		2"1 37/64"185191831A174000000
     

    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
    Image of Product. Front orientation. Hex Nuts. Thin-Profile Hex Nuts.
    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
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1 3/8"-6
    		2 1/16"25/32"SAE Grade 5
    		ASME B18.2.2194846A440000000
     
    High-Strength Steel
    Image of Product. Front orientation. Hex Nuts. Thin-Profile 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.
    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.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Specs. Met
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Zinc-Yellow-Chromate-Plated Steel
    1 3/8"-6
    		2 1/16"25/32"SAE Grade 8
    		ASME B18.2.2—193839A660000000
     
    Steel
    1 3/8"-6
    		2 1/16"25/32"SAE Grade 8
    		ASME B18.2.2Material Certificate
    		192052A34000000
     

    Thin-Heavy-Profile Hex Nuts

    About half the height of standard-profile hex nuts and 10% wider, these fit in spaces with low clearance and handle heavier loads by distributing them over a larger area. You can also use them as jam nuts by threading them against another hex nut to hold it in place.
    Extreme-Strength Steel
    Image of Product. Front orientation. Hex Nuts. Thin-Heavy-Profile Hex Nuts.
    These nuts are about 20% stronger than high-strength steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    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.
    Steel
    1 3/8"-6
    		2 3/16"25/32"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194195010A32000000
     

    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
    1 3/8"-6
    		2"51/64"220190566A26800000
     

    Coupling Nuts

    Image of Product. Front orientation. Coupling Nuts. Coupling Nuts.
    Also known as extension nuts, these are commonly used to connect lengths of threaded rod and join threaded parts.
    Low-Strength Steel
    Rated Grade 2 or lower, these are about half as strong as medium-strength steel coupling nuts. Use them with threaded rods that have a comparable strength rating to avoid stripping threads during installation.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Each
    Thread
    Size
    Lg.
    Wd.
    Threading
    Min. Thread
    Lg.
    1-9
    10-49
    50-Up
    Steel
    1 3/8"-6
    		8"2 1/4"Partially Threaded3 7/8"90264A704000000000000000000
     
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