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    26 Products
    About Hex Nuts
    industrial info icon

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

    Hex Nuts

    Image of Product. Front orientation. Hex Nuts. Hex Nuts.
    The most commonly used hex nuts, these are suitable for fastening most machinery and equipment.
    Medium-Strength Steel
    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.
    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.
    Thread
    Size
    Wd.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M48 × 5 mm7538ISO Class 8
    		DIN 9341000000000000000
     
    Zinc-Yellow-Chromate-Plated Steel
    M48 × 5 mm7538ISO Class 8
    		DIN 934100000000000000
     
    Black-Oxide Steel
    M48 × 5 mm7538ISO Class 8
    		DIN 934100000000000000
     
    Steel
    M48 × 3 mm7538ISO Class 8
    		DIN 934100000000000000
    M48 × 5 mm7538ISO Class 8
    		DIN 934100000000000000
     
    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.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Steel
    M48 × 5 mm7538ISO Class 10
    		DIN 9341000000000000000
     
    Extreme-Strength Steel
    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.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Steel
    M48 × 5 mm7538ISO Class 12
    		DIN 9341000000000000000
     
    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.
    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.,
    mm
    Ht.,
    mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    M48 × 5 mm7538DIN 9341000000000000000
     
    Highly-Corrosion-Resistant 316 Stainless Steel
    M48 × 5 mm7538DIN 934100000000000000
     
    Corrosion-Resistant Stainless Steel with Material Certificate
    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.
    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.,
    mm
    Ht.,
    mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Black-Oxide 18-8 Stainless Steel
    M48 × 5 mm7538DIN 9341000000000000000
     
    Low-Strength Steel with Material Certificate
    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.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    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.,
    mm
    Ht.,
    mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Black-Oxide Steel
    M48 × 5 mm7538DIN 9341000000000000000
     
    Steel
    M48 × 5 mm7538DIN 934100000000000000
     

    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.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M48 × 5 mm7524ISO Class 04
    		DIN 439B, ISO 40351000000000000000
     
    Steel
    M48 × 1.5 mm7518—DIN 936100000000000000
    M48 × 3 mm7518—DIN 936100000000000000
    M48 × 3 mm7524ISO Class 04
    		DIN 439B, ISO 4035100000000000000
    M48 × 5 mm7518—DIN 936100000000000000
    M48 × 5 mm7524ISO Class 04
    		DIN 439B, ISO 4035100000000000000
     

    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.
    Medium-Strength Steel
    Image of Product. Front orientation. Locknuts. Nylon-Insert Locknuts.
    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.
    Thread
    Size
    Wd.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M48 × 3 mm7548ISO Class 8
    		220DIN 985, ISO 105111000000000000000
    M48 × 5 mm7548ISO Class 8
    		220DIN 985, ISO 10511100000000000000
     

    Heavy-Profile Hex Nuts

    Image of Product. Front orientation. Hex Nuts. 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.
    Extreme-Strength Steel
    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.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Steel
    M48 × 3 mm8048ASTM Grade 2H
    		ASTM A194
    		1000000000000000
    M48 × 5 mm8048ASTM Grade 2H
    		ASTM A194
    		100000000000000
     

    Bearing Locknuts

    Image of System. Front orientation. Contains Annotated. Bearing Nuts. Bearing Locknuts.
    Image of Product. Carbon Steel. Front orientation. Bearing Nuts. Bearing Locknuts, Chamfered Face, Carbon Steel.

    Carbon Steel

    With a nylon insert that grips your threaded shaft or spindle without damaging its threads, these locknuts—also called shaft nuts—hold bearings, bushings, gears, and pulleys prone to vibration tightly in place. They come as one piece, so you can easily clamp them onto your shaft or spindle. But, since they aren’t made entirely of metal, they don’t stand up to heat as well as all-metal locknuts. Slots in their sides mean you can tighten and loosen them with a spanner wrench or spanner socket. Their face is also chamfered to help keep the size and weight of your assembly at a minimum. All meet international standards for bearing locknut dimensions.
    Zinc-Plated Carbon Steel—Zinc-plated carbon steel locknuts resist rusting from some moisture, but you shouldn’t use them with salt water or chemicals. They are strong and resist wear, though they don’t stand up to corrosion as well as 303 stainless steel locknuts.
    Thread Spacing—When choosing your thread spacing, consider the precision of your application. The finer the threads, the more control you have when making adjustments.
    Thread
    Zinc-Plated
    Carbon Steel
    Size
    Spacing
    OD,
    mm
    Wd.,
    mm
    Insert Max.
    Temp., ° F
    Each
    Chamfered Face
    M48 × 1.5 mmExtra Fine
    		6413.52100000000000000
     

    Thin-Profile Bearing Nuts

    Image of System. Front orientation. Contains Annotated. Bearing Nuts. Thin-Profile Bearing Nuts.
    Image of Product. Front orientation. Bearing Nuts. Thin-Profile Bearing Nuts.
    Used in pairs or with another bearing nut, these thin-profile nuts—often called shaft nuts—hold bearings, bushings, pulleys, and gears in place on your threaded shaft or spindle. Threading two nuts tightly against each other makes it harder for vibration to loosen your assembly than if you used only one nut. For the nut closer to the bearing, position the stepped face towards the bearing. These thin-profile nuts have holes on the side, so you can tighten and loosen them with a pin spanner wrench. All meet DIN 1816, an international standard for bearing locknut dimensions.
    Carbon Steel—Carbon steel bearing nuts are strong and resist wear.
    Thread Spacing—When choosing your thread spacing, consider the precision of your application. The finer the threads, the more control you have when making adjustments.
    Thread
    Size
    Spacing
    OD,
    mm
    Wd.,
    mm
    Specs.
    Met
    Each
    Carbon Steel
     
    Stepped Face
    M48 × 1.5 mmExtra Fine
    		7513DIN 18160000000000000
     

    Locknuts for use with Cotter Pins

    Use these locknuts to secure rotating parts subjected to mild vibration, such as the wheels on carts and hand trucks. They’re not recommended for use on parts exposed to high vibration because the pin can shear under prolonged stress. These nuts are reusable, but you'll need a new cotter pin (not included) with each use.
    Medium-Strength Steel
    Image of ProductInUse. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    Image of Product. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    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.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    For Cotter
    Pin Dia., mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Steel
    M48 × 5 mm7550ISO Class 8
    		8DIN 9351000000000000000
     

    T-Slot Nuts

    Image of Product. Front orientation. Contains Annotated. T-Slot Nuts.
    Slide into T-slot tracks on machine tool tables to secure clamps and workpieces. These nuts are often paired with setup studs for adjustable fixtures.
    Metric
    Black-Oxide Steel—Create a finished look with a dark, matte coating. These nuts offer minimal corrosion resistance, so they're best for dry environments.
    Fully Threaded—Fully threaded nuts allow a stud to extend beyond the bottom of the nut.
    DIN 508—Nuts meet DIN dimensional and material requirements. Slide them into DIN 650 T-slots.
    Base,
    mm
    Fully Threaded
    For Slot
    Wd., mm
    Thread
    Size
    Lg.
    Wd.
    Ht.
    Overall
    Ht., mm
    Specs.
    Met
    Each
    Black-Oxide Steel
    54M48 × 5 mm85853470DIN 5080000000000000000
     
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