McMaster-Carr logo
    Enter e-mail addresses in the fields below
    Message
    Cancel
    Comments
    E-mail address (if you would like a response)
    9 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.
    Wd.
    Threading
    Min. Thread
    Lg.
    1-9
    10-49
    50-Up
    Zinc-Plated Steel
    1 1/2"-6
    3 1/2"2"Fully Threaded90264A290000000000000000000
    1 1/2"-6
    8"2 3/8"Partially Threaded3 7/8"90264A703000000000000000
     
    Black-Oxide Steel
    1 1/2"-6
    4"2"Fully Threaded91034A423000000000000000
     
    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.
    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
    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.
    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.
    Wd.
    Fastener Strength
    Grade/Class
    Threading
    Certificate Type
    1-9
    10-49
    50-Up
    Zinc-Plated Steel
    1 1/2"-6
    3 1/2"2 1/4"SAE Grade 8
    Fully ThreadedMaterial Certificate
    90983A251000000000000000000
     
    Extreme-Strength Steel
    Image of Product. Front orientation. Coupling Nuts. Coupling Nuts.
    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.
    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.
    Wd.
    Fastener Strength
    Grade/Class
    Threading
    Certificate Type
    1-9
    10-49
    50-Up
    Steel
    1 1/2"-6
    3 1/2"2 1/2"ASTM Grade 2H
    Fully ThreadedMaterial Certificate
    90654A3510000000000000000000
     
    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.
    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
    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.
    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
     
    back to top