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    13 Products

    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
    10-49
    50-Up
    Zinc-Plated Steel
    M20 × 2.5 mm6030Fully ThreadedDIN 633493355A390000000000000000
     
    Black-Oxide Steel
    M20 × 2.5 mm5132Fully Threaded—93020A78500000000000000
     
    Medium-Strength Steel
    Image of Product. Front orientation. Coupling Nuts. Coupling Nuts.
    These Grade 5 or Class 8 nuts are about twice as strong as low-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
    Fastener Strength
    Grade/Class
    Threading
    Specs. Met
    1-9
    10-49
    50-Up
    Zinc-Plated Steel
    M20 × 2.5 mm6030Class 8
    		Fully ThreadedDIN 633490009A2260000000000000000
     
    Black-Oxide Steel
    M20 × 2.5 mm6030Class 8
    		Fully ThreadedASME B18.2.2, DIN 633490082A121000000000000000
     
    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.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Each
    Thread Size
    Lg.,
    mm
    Wd.,
    mm
    Fastener Strength
    Grade/Class
    Threading
    Specs.
    Met
    1-9
    10-49
    50-Up
    Zinc-Plated Steel
    M20 × 2.5 mm6030Class 10
    		Fully ThreadedDIN 633490331A557000000000000000000
     
    Steel
    M20 × 2.5 mm6030Class 10
    		Fully ThreadedDIN 633497778A150000000000000000
     
    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.
    Highly Corrosion-Resistant 316 Stainless Steel—The most corrosion-resistant stainless steel coupling nuts we offer, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Each
    Thread Size
    Lg.,
    mm
    Wd.,
    mm
    Threading
    Min. Thread
    Lg., mm
    Specs.
    Met
    1-9
    10-49
    50-Up
    18-8 Stainless Steel
    M20 × 2.5 mm6030Fully Threaded—DIN 633493590A113000000000000000000
    M20 × 2.5 mm12030Partially Threaded20—90268A464000000000000000000
     
    Highly Corrosion-Resistant 316 Stainless Steel
    M20 × 2.5 mm6030Fully Threaded—DIN 633490111A338000000000000000
     
    Brass
    Image of Product. Front orientation. Coupling Nuts. Coupling Nuts.
    Brass—With a warm, polished look, these nuts are often chosen for their appearance. Similar to 18-8 stainless steel, brass is corrosion resistant enough to stand up to wet environments. It is also softer than other metals, so it's easier to thread together.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Each
    Thread Size
    Lg.,
    mm
    Wd.,
    mm
    Threading
    1-9
    10-49
    50-Up
    Brass
    M20 × 2.5 mm6030Fully Threaded90465A423000000000000000000
     

    Round Coupling Nuts

    Image of Product. Front orientation. Coupling Nuts. Round Coupling Nuts.
    Less bulky than hex coupling nuts, these have a smooth, round body that fits in tight spots. Their finished appearance makes them a common choice for decorative applications. Tighten by hand, or use soft-jaw pliers to avoid marring the outside surface. Also known as extension nuts, they are commonly used to connect lengths of threaded rod and join threaded parts.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    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.
    Each
    Thread Size
    Lg.,
    mm
    OD,
    mm
    Threading
    Specs.
    Met
    1-9
    10-Up
    18-8 Stainless Steel
    M20 × 2.5 mm5028Fully ThreadedASTM A58290202A123000000000000
     

    Reinforced Threaded-Hole Bumpers

    Image of Product. Front orientation. Bumpers. Reinforced Threaded-Hole Bumpers, Style 1.

    Style 1

    With a metal base plate for added strength, these bumpers withstand repeated impacts for a longer service life than all-rubber bumpers. You can also use them as spacers and noise reducers. Twist them onto a threaded stud on your equipment, or pair them with your own stud to create a custom-length bumper.
    Abrasion-Resistant Polyurethane RubberAbout Abrasion-Resistant Polyurethane Rubber
    Image of Product. Front orientation. Bumpers. Reinforced Threaded-Hole Bumpers, Style 1.

    Style 1

    Our toughest rubber bumpers, they keep their shape even when knocked and scraped by metal and other abrasive materials. They're often used on industrial vehicles, conveyors, and heavy construction equipment.
    Hardness Rating—The harder the bumper, the better it withstands impact and abrasion over time. The softer the bumper, the more cushioning it provides for objects made of glass, soft metal, and other fragile materials. Bumpers with a medium rating offer a balance of impact resistance and cushioning.
    Thread
    Size
    Dp.,
    mm
    OD,
    mm
    Ht.,
    mm
    Hardness
    Hardness
    Rating
    Color
    Temp.,
    ° F
    Base Plate
    Material
    Nonmarking
    For Use
    Outdoors
    Each
    Style 1
    M20 × 2.5 mm255757Durometer 95AExtra HardBlack-40 to 200SteelNoYes9546K494000000
     

    High-Profile Hex Nuts

    Image of Product. Bottom orientation. Hex Nuts. High-Profile Hex Nuts.
    Slightly taller than standard-profile hex nuts, these have a larger gripping area so your wrench or socket won't slip off as you tighten them. They're often used in vehicles and machinery where fasteners can be difficult to reach.
    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.
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M20 × 2.5 mm3020Class 8
    		590725A740000000
     
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