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    18 Products

    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
    M18 × 2.5 mm279Class 04DIN 439B, ISO 40351090695A153000000
     
    Steel
    M18 × 2.5 mm279—DIN 9361090370A10700000
    M20 × 2.5 mm309—DIN 9361090370A10800000
     
    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
    M18 × 2.5 mm279DIN 439B, ISO 4035590710A150000000
    M18 × 2.5 mm279DIN 936590381A10500000
    M20 × 2.5 mm309DIN 936190381A1060000
     
    Black-Oxide 18-8 Stainless Steel
    M18 × 2.5 mm279DIN 439B, ISO 4035196315A1230000
     
    Highly Corrosion-Resistant 316 Stainless Steel
    M18 × 2.5 mm279DIN 936197289A1160000
    M20 × 2.5 mm309DIN 936197289A1170000
     

    Weld Nuts

    Image of Product. Top orientation. Weld Nuts. Weld Nuts.
    Image of Product. Bottom orientation. Weld Nuts. Weld Nuts.
    Add permanent threads to thin metal with our go-to weld nuts. Unlike press-fit and rivet nuts, these nuts fuse to the base metal, so they won’t twist and pull out. Three evenly spaced projections concentrate heat away from the threads to prevent them from deforming and create consistent welds. All have a collar pilot that guides the nut into the hole, holds it in place while welding, and protects the threads from weld spatter. You can also install them on thick pieces of metal.
    Steel—Best for dry environments since moisture will cause them to rust. Made of uncoated steel, these nuts require minimal prep. Weld them to uncoated steel surfaces.
    18-8 Stainless Steel—Suitable for outdoor use, these nuts resist rust from water and mild chemicals. Weld them to stainless steel surfaces.
    Collar,
    mm
    Thread
    Size
    Wd.,
    mm
    Ht.,
    mm
    Dia.
    Ht.
    For Hole
    Dia., mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Steel
    M4 × 0.7 mm92.8560.656DIN 92910093337A500000000
     
    18-8 Stainless Steel
    M4 × 0.7 mm92.960.656DIN 9295093418A3000000
     

    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.
    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
    Zinc-Plated Steel
    M3 × 0.5 mm9 mm6 mmFully Threaded—93355A530000000000000000
     
    Black-Oxide Steel
    M3 × 0.5 mm9 mm6 mmFully Threaded—93020A103000000000000
     
    Steel
    2"-4 1/2
    		9"3 1/4"Partially Threaded4 3/8"90264A706000000000000000000
     
    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.
    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.
    Each
    Thread
    Size
    Lg.,
    mm
    Wd.,
    mm
    Threading
    1-9
    10-49
    50-Up
    18-8 Stainless Steel
    M3 × 0.5 mm95Fully Threaded93590A103000000000000000
     
    Black-Oxide 18-8 Stainless Steel
    M3 × 0.5 mm95Fully Threaded93590A319000000000000
     

    High-Profile Flange Nuts

    Image of Product. Bottom orientation. Flange Nuts. High-Profile Flange Nuts.
    30% taller than standard-profile nuts, these have a large gripping area so your wrench or socket won't slip off as you tighten them. They also engage more threads for extra gripping power. Nuts have a flange that distributes pressure evenly across the mounting surface without the need for a separate washer. They are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. Also known as collar nuts.
    High-Strength Steel
    Rated Grade 8, Grade G, or Class 10, these are about 25% stronger than medium-strength steel nuts. They are commonly used to fasten components in valves, pumps, and motors. 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.
    Flange,
    mm
    Thread
    Size
    Wd.,
    mm
    Ht.,
    mm
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Steel
    M6 × 1 mm109143Class 10DIN 63315090360A111000000
     

    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.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    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
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Black-Oxide Steel
    M18 × 2.5 mm279Class 04ASTM A108, DIN 439B, ISO 4035Material Certificate
    		190519A82100000
     
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