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    23 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.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M3 × 0.5 mm5.51.8ISO Class 04
    		DIN 439B, ISO 403510000000000000000
     
    Steel
    M3 × 0.5 mm5.51.8—DIN 439B, ISO 40351000000000000000
     
    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.
    Thread
    Size
    Wd.,
    mm
    Ht.,
    mm
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    M3 × 0.5 mm5.51.8DIN 439B, ISO 4035100000000000000000
     
    Black-Oxide 18-8 Stainless Steel
    M3 × 0.5 mm5.51.8DIN 439B, ISO 4035100000000000000
     
    Highly-Corrosion-Resistant 316 Stainless Steel
    M3 × 0.5 mm5.51.8DIN 439B, ISO 403510000000000000000
     
    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.
    Nickel-Plated Brass—The nickel plating offers better corrosion resistance than plain brass to stand up to solvents, salt water, and chemicals. The plating can wear off over time, so these nuts are not recommended for applications that experience a lot of friction or wear.
    Thread
    Size
    Wd.,
    mm
    Ht.,
    mm
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Brass
    M3 × 0.5 mm5.51.8DIN 439B, ISO 4035100000000000000000
     
    Nickel-Plated Brass
    M3 × 0.5 mm5.51.8DIN 439B, ISO 4035250000000000000
     

    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.,
    mm
    Ht.,
    mm
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M3 × 0.5 mm5.53.9245ISO 105112500000000000000
     

    Medium-Strength Steel Thin-Profile Square Nuts

    Image of Product. Front orientation. Square Nuts. Medium-Strength Steel Thin-Profile Square Nuts.
    Made of ISO Class 04 steel and about two-thirds the height of standard steel square nuts, these nuts are suitable for most low-clearance fastening applications. Also known as square jam nuts, they’re commonly jammed together to hold each other in place. Their flat, broad sides make them easy to grip with a wrench and keep them from rotating in channels and square holes. Compared to hex nuts, a greater area is in contact with the fastened surface.
    Black-Oxide Steel—Black-oxide steel square nuts have a dark surface color and are mildly corrosion resistant in dry environments.
    Zinc-Plated Steel—Zinc-plated steel square nuts resist corrosion in wet environments.
    DIN 562—These nuts meet DIN 562, an international standard that signifies their material and dimensions are compatible with other products and tools.
    Thread
    Size
    Wd.,
    mm
    Ht.,
    mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Black-Oxide Steel—ISO Class 04
    M3 × 0.5 mm5.51.8DIN 5621000000000000000
     
    Zinc-Plated Steel—ISO Class 04
    M3 × 0.5 mm5.51.8DIN 5621000000000000000
     

    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
    M3 × 0.5 mm5.51.8ISO 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
    M3 × 0.5 mm5.51.8DIN 439B100000000000000
     
    Corrosion-Resistant Stainless Steel with Material Certificate
    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
    M3 × 0.35 mm5.51.8DIN 439B100000000000000
     

    Knurled-Head Thumb Nuts

    Image of Attribute. Front orientation. Contains Annotated. Thumb Nuts. Knurled-Head Thumb Nuts.
    Get a good grip on these nuts, even with oily fingers. They have a raised, slip-resistant head, so you can tighten them by hand and make controlled adjustments. Knurled-head nuts have a smaller profile than wing nuts, so they fit in tighter spots.
    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.
    Collar,
    mm
    Thread
    Size
    Dia.
    Ht.
    Head Dia.,
    mm
    Ht.,
    mm
    Threading
    Specs.
    Met
    Each
    18-8 Stainless Steel
    M3 × 0.5 mm65127.5Fully ThreadedDIN 46600000000000000
     
    Black-Oxide 18-8 Stainless Steel
    M3 × 0.5 mm65127.5Fully ThreadedDIN 4660000000000000
     
    Plastic
    Reinforced Acetal—The best plastic for damp and wet environments, acetal won't swell or lose strength if exposed to moisture. These nuts are reinforced with an aluminum threaded insert, so they can handle more torque than other plastic nuts and won't crack during installation.
    Collar,
    mm
    Thread
    Size
    Dia.
    Ht.
    Head Dia.,
    mm
    Ht.,
    mm
    Color
    Threading
    Insert
    Material
    Pkg.
    Qty.
    Pkg.
    Reinforced Acetal
    M3 × 0.5 mm9.11.29.65.6BlackFully ThreadedAluminum
    		1000000000000000
     

    18-8 Stainless Steel Thin-Profile Square Nuts

    Image of Product. Front orientation. Square Nuts. 18-8 Stainless Steel Thin-Profile Square Nuts.
    Two-thirds the height of typical square nuts and made of 18-8 stainless steel, these metric nuts are designed for use in low-clearance applications in humid, damp, and washdown environments. They’re often called square jam nuts because they can be jammed together to hold each other in place. They’re easily gripped with a wrench due to their flat, broad sides, which also prevent them from rotating in channels and square holes. Compared to hex nuts, a greater area is in contact with the fastened surface. And compared to steel nuts, they’re slightly less strong.
    Black-Oxide 18-8 Stainless Steel—Black-oxide 18-8 stainless steel nuts have a dark surface color.
    DIN 562—These nuts meet DIN 562, an international standard that signifies their material and dimensions are compatible with other products and tools.
    Thread
    Size
    Wd.,
    mm
    Ht.,
    mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    M3 × 0.5 mm5.51.8DIN 5625000000000000000
     
    Black-Oxide 18-8 Stainless Steel
    M3 × 0.5 mm5.51.8DIN 5621000000000000000
     

    Flanged Knurled-Head Thumb Nuts

    Image of Attribute. Front orientation. Contains Annotated. Thumb Nuts. Flanged Knurled-Head Thumb Nuts.
    The slip-resistant head is easy to grip, while the flange distributes pressure evenly across the mounting surface without the need for a separate washer. These nuts are often used to secure screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts.
    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.
    Passivated 18-8 Stainless Steel—With an added layer of protection, these nuts stand up to strong acids and other harsh chemicals.
    Collar,
    mm
    Thread
    Size
    Dia.
    Ht.
    Head Dia.,
    mm
    Ht.,
    mm
    Threading
    Each
    18-8 Stainless Steel
    M3 × 0.5 mm6386Fully Threaded00000000000000
    M3 × 0.5 mm65168Fully Threaded0000000000000
     
    Black-Oxide 18-8 Stainless Steel
    M3 × 0.5 mm6386Fully Threaded0000000000000
     
    Passivated 18-8 Stainless Steel
    M3 × 0.5 mm6386Fully Threaded0000000000000
     
    Brass
    Zinc-Plated Brass—The zinc plating offers better corrosion resistance than plain brass to stand up to solvents and mild chemicals.
    Collar,
    mm
    Thread
    Size
    Dia.
    Ht.
    Head Dia.,
    mm
    Ht.,
    mm
    Threading
    Each
    Zinc-Plated Brass
    M3 × 0.5 mm6386Fully Threaded00000000000000
     
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