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    19 Products

    Coupling Nuts

    Image of Product. Front orientation. Coupling Nuts. Coupling Nuts.
    Also known as extension nuts, these are commonly used to connect lengths of threaded rod and join threaded parts.
    Low-Strength Steel
    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.
    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. Use with other hot-dipped galvanized fasteners to ensure the threads mate tightly.
    Each
    Thread
    Size
    Lg.
    Wd.
    Threading
    Min. Thread
    Lg.
    1-9
    10-Up
    Zinc-Plated Steel
    1 1/4"-7
    		3"1 5/8"Fully Threaded—000000000000000000000
    1 1/4"-7
    		7 1/2"2"Partially Threaded3 5/8"0000000000000000000
     
    Black-Oxide Steel
    1 1/4"-7
    		3"1 5/8"Fully Threaded—0000000000000000000
     
    Hot-Dipped Galvanized Steel
    1 1/4"-7
    		3"1 5/8"Fully Threaded—0000000000000000000
     
    Medium-Strength Steel
    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.
    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. Use with other hot-dipped galvanized fasteners to ensure the threads mate tightly.
    Each
    Thread
    Size
    Lg.
    Wd.
    Fastener Strength
    Grade/Class
    Threading
    1-9
    10-Up
    Zinc-Plated Steel
    1 1/4"-7
    		3"1 5/8"SAE Grade 5
    		Fully Threaded000000000000000000000
     
    Hot-Dipped Galvanized Steel
    1 1/4"-7
    		3"1 5/8"SAE Grade 5
    		Fully Threaded0000000000000000000
     
    High-Strength Steel
    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.
    Wd.
    Fastener Strength
    Grade/Class
    Threading
    1-9
    10-Up
    Zinc-Plated Steel
    1 1/4"-7
    		3"1 7/8"SAE Grade 8
    		Fully Threaded000000000000000000000
     
    Extreme-Strength Steel
    Made from Grade 2H steel, these are about 20% stronger than high-strength steel coupling nuts. Use them with threaded rods that have a comparable strength rating to avoid stripping threads during installation.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Each
    Thread
    Size
    Lg.
    Wd.
    Fastener Strength
    Grade/Class
    Threading
    1-9
    10-Up
    Steel
    1 1/4"-7
    		3"2"ASTM Grade 2H
    		Fully Threaded000000000000000000000
     
    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.
    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.
    Wd.
    Threading
    1-9
    10-Up
    18-8 Stainless Steel
    1 1/4"-7
    		3"1 5/8"Fully Threaded000000000000000000000
     
    Highly-Corrosion-Resistant 316 Stainless Steel
    1 1/4"-7
    		3"1 5/8"Fully Threaded000000000000000000000
     

    Inch-to-Inch Female Hex Thread Adapters

    Image of Product. Front orientation. Contains Annotated. Thread Adapters. Inch-to-Inch Female Hex Thread Adapters.
    Image of Attribute. Front orientation. Contains Annotated. Thread Adapters. Inch-to-Inch Female Hex Thread Adapters.
    Connect two differently sized male-threaded parts, such as threaded rods, and tighten with a standard wrench. The threads on these adapters have various sizes and spacing, so you can increase or decrease thread size or adapt from coarse to fine threading. You can also use them to change the gender of a connection from male to female. Small adapters can work as threaded standoffs, which position and separate circuit boards and other components in assemblies.
    Zinc-Plated Steel—Zinc-plated steel adapters resist corrosion until the plating wears away and are often used in dry environments.
    18-8 Stainless Steel—18-8 stainless steel adapters withstand wet environments but will corrode when exposed to salt water and other chloride solutions.
    316 Stainless Steel—316 stainless steel adapters are ideal in wet environments and will not corrode when exposed to salt water or harsh chemicals.
    ASTM A108, ASTM A276, ASTM A582, and ASTM B633—Adapters that meet ASTM specifications are made from or plated with materials that adhere to specific standards for chemical and physical properties, such as hardness.
    Thread
    Lg.
    Thread
    Fit
    Hex
    Each
    Thread Size
    (A)
    Thread Size
    (B)
    (A)
    (B)
    (A)
    (B)
    Size
    Length
    Specs. Met
    Tensile Strength,
    psi
    Hardness
    1-9
    10-Up
    Zinc-Plated Steel
    3/4"-10
    		1 1/4"-7
    		3/4"1 1/16"Unified Standard Class 2B
    		Unified Standard Class 2B
    		1 5/8"3"ASTM A108, ASTM B63375,000Rockwell B65000000000000000000000
    7/8"-9
    		1 1/4"-7
    		7/8"1 1/16"Unified Standard Class 2B
    		Unified Standard Class 2B
    		1 5/8"3"ASTM A108, ASTM B63375,000Rockwell B650000000000000000000
    1"-8
    		1 1/4"-7
    		1"1 1/16"Unified Standard Class 2B
    		Unified Standard Class 2B
    		1 5/8"3"ASTM A108, ASTM B63375,000Rockwell B650000000000000000000
     
    18-8 Stainless Steel
    3/4"-10
    		1 1/4"-7
    		3/4"1 1/16"Unified Standard Class 2B
    		Unified Standard Class 2B
    		1 5/8"3"ASTM A58285,000Rockwell B800000000000000000000
    7/8"-9
    		1 1/4"-7
    		7/8"1 1/16"Unified Standard Class 2B
    		Unified Standard Class 2B
    		1 5/8"3"ASTM A58285,000Rockwell B800000000000000000000
    1"-8
    		1 1/4"-7
    		1"1 1/16"Unified Standard Class 2B
    		Unified Standard Class 2B
    		1 5/8"3"ASTM A58285,000Rockwell B800000000000000000000
     
    316 Stainless Steel
    3/4"-10
    		1 1/4"-7
    		3/4"1 1/16"Unified Standard Class 2B
    		Unified Standard Class 2B
    		1 5/8"3"ASTM A27675,000Rockwell B830000000000000000000
     

    Left-Hand to Right-Hand Female Hex Thread Adapters

    Image of Product. Front orientation. Contains Annotated. Thread Adapters. Left-Hand to Right-Hand Female Hex Thread Adapters.
    Image of Attribute. Front orientation. Contains Annotated. Thread Adapters. Left-Hand to Right-Hand Female Hex Thread Adapters.
    Often called sleeve nuts, these thread adapters fasten parts with right-hand threads to parts with left-hand threads.
    Zinc-Plated Steel—Zinc-plated steel adapters are strong and corrosion resistant.
    Thread
    Lg.
    Thread
    Fit
    Hex
    Each
    Thread Size
    (A)
    Thread Size
    (B)
    (A)
    (B)
    (A)
    (B)
    Size
    Length
    Hardness
    1-9
    10-Up
    Zinc-Plated Steel
    1 1/4"-7
    		1 1/4"-7
    		3 1/2"3 1/2"Unified Standard Class 2B
    		Unified Standard Class 2B
    		2"7 1/2"Rockwell B65000000000000000000000
     

    Left-Hand-Thread Coupling Nuts

    Image of Product. Front orientation. Contains Annotated, MultipleImages. Coupling Nuts. Left-Hand-Thread Coupling Nuts.
    Pair with left-hand threaded rods, and turn to the left to tighten. Also known as extension nuts, these are commonly used to connect lengths of threaded rod and join threaded parts.
    Low-Strength Steel
    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.
    Each
    Thread
    Size
    Lg.
    Wd.
    Threading
    1-9
    10-Up
    Zinc-Plated Steel
    1 1/4"-7
    		3"1 5/8"Fully Threaded000000000000000000000
     
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