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    9 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.
    Each
    Thread
    Size
    Lg.
    Wd.
    Threading
    Min. Thread
    Lg.
    1-9
    10-49
    50-Up
    Zinc-Plated Steel
    1 1/2"-6
    		3 1/2"2"Fully Threaded—90264A290000000000000000000
    1 1/2"-6
    		8"2 3/8"Partially Threaded3 7/8"90264A703000000000000000
     
    Black-Oxide Steel
    1 1/2"-6
    		4"2"Fully Threaded—91034A423000000000000000
     
    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.
    Each
    Thread
    Size
    Lg.
    Wd.
    Fastener Strength
    Grade/Class
    Threading
    1-9
    10-49
    50-Up
    Zinc-Plated Steel
    1 1/2"-6
    		3 1/2"2"SAE Grade 5
    		Fully Threaded90977A245000000000000000000
     
    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
    10-49
    50-Up
    Zinc-Plated Steel
    1 1/2"-6
    		3 1/2"2 1/4"SAE Grade 8
    		Fully Threaded90983A251000000000000000000
     
    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
    10-49
    50-Up
    Steel
    1 1/2"-6
    		3 1/2"2 1/2"ASTM Grade 2H
    		Fully Threaded90654A351000000000000000000
     
    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.
    Wd.
    Threading
    1-9
    10-49
    50-Up
    18-8 Stainless Steel
    1 1/2"-6
    		3 1/2"2"Fully Threaded90268A513000000000000000000
     
    Brass
    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.
    Each
    Thread
    Size
    Lg.
    Wd.
    Threading
    1-9
    10-49
    50-Up
    Brass
    1 1/2"-6
    		3 1/2"2"Fully Threaded90465A33300000000000000000000
     

    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 1/2"-6
    		1 1/2"-6
    		3 3/4"3 3/4"Unified Standard Class 2B
    		Unified Standard Class 2B
    		2 3/8"8"Rockwell B6594280A104000000000000
     
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