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    4 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.
    Each
    Thread
    Size
    Lg.
    Wd.
    Threading
    1-9
    10-49
    50-Up
    Zinc-Plated Steel
    9/16"-12
    		2 1/8"13/16"Fully Threaded000000000000000000000000
     
    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
    Min. Thread
    Lg.
    1-9
    10-49
    50-Up
    18-8 Stainless Steel
    9/16"-12
    		2 1/8"13/16"Fully Threaded—000000000000000000000000000
    9/16"-12
    		5"7/8"Partially Threaded3/4"000000000000000000000000
     
    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
    9/16"-12
    		2 1/8"13/16"Fully Threaded000000000000000000000000000
     
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