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    56 Products

    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.
    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
    M27 × 2 mm4122ISO Class 8
    		DIN 9341000000000000000
    M27 × 3 mm4122ISO Class 8
    		DIN 93410000000000000
     
    Zinc-Yellow-Chromate-Plated Steel
    M27 × 3 mm4122ISO Class 8
    		DIN 93410000000000000
     
    Black-Oxide Steel
    M27 × 3 mm4122ISO Class 8
    		DIN 934100000000000000
     
    Steel
    M27 × 1.5 mm4122ISO Class 8
    		DIN 934100000000000000
    M27 × 2 mm4122ISO Class 8
    		DIN 93410000000000000
    M27 × 3 mm4122ISO Class 8
    		DIN 93410000000000000
     
    High-Strength Steel
    Image of Product. 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
    M27 × 2 mm4122ISO Class 10
    		DIN 93410000000000000
    M27 × 3 mm4122ISO Class 10
    		DIN 93410000000000000
     
    Steel
    M27 × 2 mm4122ISO Class 10
    		DIN 9341000000000000
    M27 × 3 mm4122ISO Class 10
    		DIN 934500000000000000
     
    Extreme-Strength Steel
    Image of Product. 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
    M27 × 3 mm4122ISO Class 12
    		DIN 9341000000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. 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.
    Super-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.
    Super-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.,
    mm
    Ht.,
    mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    M27 × 2 mm4120.7DIN 9341000000000000000
    M27 × 3 mm4122DIN 93410000000000000
     
    Black-Oxide 18-8 Stainless Steel
    M27 × 1.5 mm4122DIN 934100000000000000
    M27 × 3 mm4122DIN 93410000000000000
     
    Super-Corrosion-Resistant 316 Stainless Steel
    M27 × 3 mm4120.7DIN 93410000000000000
     
    Super-Corrosion-Resistant Black-Oxide 316 Stainless Steel
    M27 × 3 mm4122DIN 934100000000000000
     
    Brass
    Image of Product. Front orientation. Hex Nuts. 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.
    Thread
    Size
    Wd.,
    mm
    Ht.,
    mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Brass
    M27 × 3 mm4122DIN 9341000000000000000
     

    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.
    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
    M27 × 2 mm4113.5ISO Class 04
    		DIN 439B, ISO 4035100000000000000
    M27 × 3 mm4113.5ISO Class 04
    		DIN 439B, ISO 4035500000000000000
     
    Steel
    M27 × 1.5 mm4112—DIN 93610000000000000
    M27 × 1.5 mm4113.5ISO Class 04
    		DIN 439B, ISO 4035100000000000000
    M27 × 2 mm4112—DIN 93610000000000000
    M27 × 2 mm4113.5ISO Class 04
    		DIN 439B, ISO 403510000000000000
    M27 × 3 mm4112—DIN 93610000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Hex Nuts. Thin-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.
    Super-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
    M27 × 1.5 mm4112DIN 9361000000000000000
    M27 × 3 mm4112DIN 936100000000000000
     
    Super-Corrosion-Resistant 316 Stainless Steel
    M27 × 2 mm4113.5DIN 439B, ISO 4035100000000000000
    M27 × 3 mm4112DIN 936100000000000000
     

    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
    Image of Product. Front orientation. Contains Annotated, MultipleImages. Hex Nuts. Left-Hand-Thread 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.
    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.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Black-Oxide Steel
    M27 × 1.5 mm4113.5ISO Class 04
    		ASTM A108, DIN 439B, ISO 40351000000000000000
    M27 × 2 mm4113.5ISO Class 04
    		ASTM A108, DIN 439B, ISO 4035100000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Contains Annotated, MultipleImages. Hex Nuts. Left-Hand-Thread Thin-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.
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    M27 × 1.5 mm4113.5DIN 439B1000000000000000
    M27 × 2 mm4113.5DIN 439B100000000000000
     

    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.
    High-Strength Steel
    Image of Product. Front orientation. Hex Nuts. Heavy-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.
    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.
    Thread
    Size
    Wd.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Hot-Dipped Galvanized Steel
    M27 × 3 mm4622ISO Class 10
    		DIN 6915, ISO 74141000000000000000
     
    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.
    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
    M27 × 3 mm4627ASTM Grade 2H
    		ASTM A194, DIN 6915100000000000000
     

    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
    M27 × 3 mm4127ISO Class 10
    		220DIN 9851000000000000000
     
    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
    M27 × 1.5 mm4127ISO Class 8
    		220DIN 985, ISO 105111000000000000000
    M27 × 2 mm4127ISO Class 8
    		220DIN 985, ISO 10511100000000000000
    M27 × 3 mm4127ISO Class 8
    		220DIN 985, ISO 10511100000000000000
     
    Low-Strength Steel
    Image of Product. Front orientation. Locknuts. Nylon-Insert Locknuts.
    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.,
    mm
    Ht.,
    mm
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M27 × 3 mm4127220100000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Locknuts. Nylon-Insert Locknuts.
    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.
    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.,
    mm
    Ht.,
    mm
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    M27 × 3 mm4127220DIN 9851000000000000000
     
    316 Stainless Steel
    M27 × 3 mm4127220DIN 985100000000000000
     

    Top-Lock Distorted-Thread Locknuts

    Irregularly shaped threads at the top of these locknuts grip the screw for a stronger hold than nylon-insert locknuts. Although the threads prevent the nut from backing out due to vibration, they also increase the effort to install and remove. To get these nuts off, you may need special tools, such as an impact wrench or propane torch. Nuts are not reusable.
    High-Strength Steel
    Image of Product. Front orientation. Locknuts. Top-Lock Distorted-Thread 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
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M27 × 3 mm4127ISO Class 10
    		100000000000000
     
    Medium-Strength Steel
    Image of Product. Front orientation. Locknuts. Top-Lock Distorted-Thread 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
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M27 × 3 mm4127ISO Class 8
    		DIN 980V100000000000000
     

    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.
    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
    For Cotter
    Pin Dia., mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M27 × 3 mm4130ISO Class 8
    		5DIN 9351000000000000000
     

    Steel-Insert Locknuts for Extreme Vibration

    The most secure hold of all the locknuts we offer. The tab on the insert stops the nut from rotating, even under extreme vibration. These locknuts are ideal for equipment with constant motion or jarring starts and stops, including conveyors, shakers, and compactors. In fact, they're so secure that they're even used to fasten components on roller coasters. These locknuts are also reusable, but their holding power decreases after the first use, so you should use a new nut for the strongest possible hold.
    Medium-Strength Steel
    Image of Product. Bottom orientation. Locknuts. Steel-Insert Locknuts for Extreme Vibration.
    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
    Each
    Steel
    M27 × 3 mm4124.4ISO Class 8
    		000000000000000
     

    Bearing Locknuts

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

    Zinc-Plated

    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
    M27 × 1.5 mmExtra Fine
    		44112100000000000000
     

    Coupling Nuts

    Also known as extension nuts, these are commonly used to connect lengths of threaded rod and join threaded parts.
    Low-Strength Steel
    Image of Product. Front orientation. Coupling Nuts. Coupling Nuts.
    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.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Black-Oxide Steel—A dark, matte coating creates a finished look. Nuts offer minimal corrosion resistance, so they're best for dry environments.
    Each
    Thread
    Size
    Lg.,
    mm
    Wd.,
    mm
    Threading
    Specs.
    Met
    1-9
    10-Up
    Zinc-Plated Steel
    M27 × 3 mm8141Fully ThreadedDIN 6334000000000000000000000
     
    Black-Oxide Steel
    M27 × 3 mm8141Fully ThreadedDIN 63340000000000000000000
     
    High-Strength Steel
    Image of Product. Front orientation. Coupling Nuts. Coupling Nuts.
    Rated Grade 8 or Class 10, these are about 25% stronger than medium-strength steel coupling nuts. Use them with threaded rods that have a comparable 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.
    Each
    Thread
    Size
    Lg.,
    mm
    Wd.,
    mm
    Fastener Strength
    Grade/Class
    Threading
    Specs.
    Met
    1-9
    10-Up
    Zinc-Plated Steel
    M27 × 3 mm8141ISO Class 10
    		Fully ThreadedDIN 6334000000000000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Coupling Nuts. Coupling 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.
    Each
    Thread
    Size
    Lg.,
    mm
    Wd.,
    mm
    Threading
    1-9
    10-Up
    18-8 Stainless Steel
    M27 × 3 mm8141Fully Threaded000000000000000000000
     

    T-Slot Nuts

    Designed to slide into T-slot tracks on machine tool tables, use these nuts to secure clamps and workpieces.
    Metric
    Image of Product. Front orientation. T-Slot Nuts. T-Slot Nuts.
    Image of Attribute. Front orientation. Contains Annotated. T-Slot Nuts.
    Fully Threaded—Fully threaded nuts allow a stud to extend beyond the bottom of the nut.
    Base,
    mm
    Fully Threaded
    Thread
    Size
    For Slot
    Wd., mm
    Ht.
    Wd.
    Overall
    Ht., mm
    Each
    Black-Oxide Steel
    M27 × 3 mm32205040000000000000000
     

    Threaded on Both Ends Setup Studs

    Known as setup studs, these studs withstand sideways forces better than fully threaded studs because they have a strong unthreaded middle. The unthreaded middle also makes more contact with unthreaded holes, creating better alignment than a fully threaded stud.
    Black-Oxide Steel
    Image of Product. Front orientation. Contains Annotated. Setup Studs.
    Black-oxide steel studs resist rusting in dry environments.
    DIN 6379—Studs that meet DIN standards meet dimensional and material requirements.
    Thread,
    mm
    Lg.
    (A)
    Lg.
    (B)
    Lg.,
    mm
    Tensile Strength,
    psi
    Specs.
    Met
    Each
    M27 × 3 mm
    5639125100,000DIN 6379000000000000000
    12239200100,000DIN 637900000000000000
    20039315100,000DIN 637900000000000000
     
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