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    10 Products

    Spring-Stop Locknuts
    3D CAD models available

    Image of Product. Front orientation. Locknuts. Spring-Stop Locknuts.
    These locknuts withstand heavy vibration similar to distorted-thread nuts, and you can use them over and over. The prongs at the top bend when tightened to create tension for a secure hold. As you remove the locknut, the prongs spring back to their original shape, so you can install the nut again without losing holding power. Also known as Fuji locknuts.
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar 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.
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M5 × 0.8 mm84.6ISO Class 6
    10000000000000000
    M6 × 1 mm105.1ISO Class 6
    1000000000000000
    M8 × 1.25 mm127.3ISO Class 6
    1000000000000000
    M10 × 1.25 mm148.5ISO Class 6
    50000000000000
    M10 × 1.5 mm178.5ISO Class 6
    1000000000000000
    M12 × 1.25 mm1710.4ISO Class 6
    10000000000000
     
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    M5 × 0.8 mm84.810000000000000000
    M6 × 1 mm105.1500000000000000
    M8 × 1.25 mm137.2500000000000000
    M10 × 1.5 mm179.210000000000000
     
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