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    4 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-Up
    Zinc-Plated Steel
    M27 × 3 mm8141Fully ThreadedDIN 633493355A570000000000000
     
    Black-Oxide Steel
    M27 × 3 mm8141Fully ThreadedDIN 633493020A1090000000000
     
    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.
    Each
    Thread
    Size
    Lg.,
    mm
    Wd.,
    mm
    Fastener Strength
    Grade/Class
    Threading
    Specs.
    Met
    1-9
    10-Up
    Zinc-Plated Steel
    M27 × 3 mm8141ISO Class 10
    		Fully ThreadedDIN 633490331A559000000000000
     
    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.,
    mm
    Wd.,
    mm
    Threading
    1-9
    10-Up
    18-8 Stainless Steel
    M27 × 3 mm8141Fully Threaded93590A315000000000000
     
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