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    28 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.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M42 × 4.5 mm6534Class 8
    		DIN 934190591A19900000
     
    Black-Oxide Steel
    M42 × 4.5 mm6534Class 8
    		DIN 934190593A02100000
     
    Steel
    M42 × 3 mm6534Class 8
    		DIN 934191423A37000000
    M42 × 4.5 mm6534Class 8
    		DIN 934190592A4720000
     
    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.
    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
    M42 × 4.5 mm6534Class 10
    		DIN 934190870A117000000
     
    Steel
    M42 × 4.5 mm6534Class 10
    		DIN 934190685A10300000
     
    Extreme-Strength Steel
    Image of Product. Front orientation. Hex Nuts. Hex Nuts.
    Image of Specification. Front orientation. Hex Nuts. 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.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Steel
    M42 × 4.5 mm6534Class 12
    		DIN 934194223A115000000
     
    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.
    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
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Black-Oxide Steel
    M42 × 4.5 mm6534DIN 934Material Certificate
    		195479A521000000
     
    Steel
    M42 × 4.5 mm6534DIN 934Material Certificate
    		195505A72100000
     
    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.
    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.
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    M42 × 4.5 mm6534DIN 934191828A465000000
     
    Black-Oxide 18-8 Stainless Steel
    M42 × 4.5 mm6534DIN 934198676A36000000
     
    Highly Corrosion-Resistant 316 Stainless Steel
    M42 × 4.5 mm6534DIN 934194150A38900000
     

    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
    M42 × 4.5 mm6521Class 04
    		DIN 439B, ISO 4035190695A156000000
     
    Steel
    M42 × 1.5 mm6516—DIN 936190364A12500000
    M42 × 3 mm6516—DIN 936190364A12400000
    M42 × 3 mm6521Class 04
    		DIN 439B, ISO 4035190326A22600000
    M42 × 4.5 mm6516—DIN 936190370A11600000
     
    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.,
    mm
    Ht.,
    mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    M42 × 4.5 mm6516DIN 936190381A114000000
     

    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.
    High-Strength Steel
    Image of Product. Front orientation. Locknuts. Nylon-Insert Locknuts.
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength steel nuts. 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
    M42 × 4.5 mm6542Class 10
    		220DIN 985194645A370000000
     
    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
    M42 × 3 mm6542Class 8
    		220DIN 985, ISO 10511190576A531000000
     

    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
    M42 × 3 mm7042ASTM Grade 2H
    		ASTM A194
    		198498A140000000
    M42 × 4.5 mm7042ASTM Grade 2H
    		ASTM A194
    		198498A11800000
     

    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
    M42 × 1.5 mmExtra Fine
    		62152103552N42000000
     

    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
    M42 × 4.5 mm6546Class 8
    		8DIN 935193760A123000000
     

    Bearing Nuts

    Image of Product. Front orientation. Bearing Nuts. Bearing Nuts, Carbon Steel, Stepped Face.

    Carbon Steel

    Stepped Face

    Often paired with spring lock washers to strengthen their hold, these bearing nuts—also known as shaft nuts—keep vibration from shifting bearings, bushings, pulleys, and gears on your threaded shaft or spindle. They have slotted sides, so you can tighten and loosen them with a spanner wrench or spanner socket.
    Carbon Steel—Carbon steel bearing nuts are strong and resist wear.
    Stepped Face—Use stepped-face bearing nuts with DIN 462 spring lock washers. You can also use them in pairs or with other bearing nuts. For the nut closer to the bearing, position the stepped face towards the bearing. All meet DIN standards for bearing lockout dimensions.
    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.
    Nuts
    Bearing
    Lock Washers
    Thread
    Size
    Spacing
    OD,
    mm
    Wd.,
    mm
    Specs.
    Met
    For Lock Washer
    Specs. Met
    Each
    Each
    Carbon Steel
     
    Stepped Face
    M42 × 1.5 mmExtra Fine
    		6212DIN 1804DIN 4623564N2600000090407A12900000
     

    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
    M42 × 1.5 mmExtra Fine
    		6212DIN 18163549N25000000
     

    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
    48M42 × 4.5 mm75753060DIN 50890510A2410000000
     
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