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    14 Products

    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
    Image of Product. Front orientation. Locknuts. Spring-Stop Locknuts.
    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
     

    Nylon-Insert Cap Nuts

    Get the protection of a cap nut with the vibration resistance of a locknut. These nuts not only conceal protruding screw threads, they also have a nylon insert that grips the screw to prevent loosening from moderate vibration. However, the insert may become brittle if exposed to high temperatures. Nuts are reusable a handful of times, but their holding power decreases with each use.
    Low-Strength Steel
    Image of Product. Bottom orientation. Cap Nuts. Nylon-Insert Cap Nuts.
    Rated Grade 2, Class 6, or lower, these nuts 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
    Thread
    Dp., mm
    Wd.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M4 × 0.7 mm2.379.6ISO Class 6
    		DIN 98624550000000000000000
    M5 × 0.8 mm3.5810.5ISO Class 6
    		DIN 986245250000000000000
    M6 × 1 mm3.91012ISO Class 6
    		DIN 986245250000000000000
    M8 × 1.25 mm5.21314ISO Class 6
    		DIN 9862452500000000000000
    M10 × 1.5 mm6.41618ISO Class 6
    		DIN 9862451000000000000000
    M12 × 1.75 mm8.31823ISO Class 6
    		DIN 98624550000000000000
    M16 × 2 mm11.32428ISO Class 6
    		DIN 98624510000000000000
    M20 × 2.5 mm13.53035ISO Class 6
    		DIN 98624510000000000000
     
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