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    13 Products

    Mil. Spec. Distorted-Thread Flange Nuts
    3D CAD models available

    Image of Product. Front orientation. Flange Nuts. Mil. Spec. Distorted-Thread Flange Nuts.
    Not only do these have the strongest hold of all the flange nuts we offer, they are also manufactured and tested to strict U.S. military standards for material and construction. They have irregularly shaped threads that grip the screw to resist loosening in high-vibration applications. The threads prevent the nut from backing out, but they also increase the effort to install and remove. To get these nuts off, you may need special tools, such as an impact wrench or propane torch, so they are not reusable. Nuts have a flange that distributes pressure evenly across the mounting surface without the need for a separate washer. They are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. Also known as collar nuts.
    Corrosion-Resistant Stainless Steel
    High-Temperature Silver-Plated A286 Stainless Steel—The silver plating reduces friction during installation, so these nuts thread on smoother than others. They are stronger than 316 stainless steel and withstand temperatures up to 800° F. Nuts resist corrosion from chemicals, such as bleach and chlorine, but won't hold up to salt water as well as 316 stainless steel.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Mil.
    Spec.
    Pkg.
    Qty.
    Pkg.
    High-Temperature Silver-Plated A286 Stainless Steel
    4-40
    5/32"1/8"0.206"0.03"MS21043-045000000000000000
    6-32
    3/16"9/64"0.244"0.03"MS21043-0650000000000000
    8-32
    7/32"3/16"0.29"0.03"MS21043-08500000000000000
    10-32
    1/4"3/16"0.33"0.03"MS21043-350000000000000
    1/4"-28
    5/16"7/32"0.42"0.04"MS21043-4500000000000000
    5/16"-24
    3/8"17/64"0.52"0.04"MS21043-510000000000000
    3/8"-24
    7/16"9/32"0.62"0.04"MS21043-610000000000000
     

    Mil. Spec. Flex-Top Locknuts for Heavy Vibration
    3D CAD models available

    Image of Product. Front orientation. Locknuts. Mil. Spec. Flex-Top Locknuts for Heavy Vibration.
    These locknuts are manufactured and tested to strict U.S. military standards for material and construction. The top section expands to grip the screw on all sides for a stronger hold than both nylon-insert and distorted-thread locknuts. As a result, they're suitable for use in equipment with constant, vigorous vibration, such as engines. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Corrosion-Resistant Stainless Steel
    Silver-Plated 18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts won't rust. The silver plating adds lubricity to help them thread on smoothly during installation.
    Thread
    Size
    Wd.
    Ht.
    Mil.
    Spec.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Silver-Plated 18-8 Stainless Steel
    4-40
    1/4"9/64"MS21046C04NASM210461000000000000000
    6-32
    5/16"11/64"MS21046C06NASM21046100000000000000
    8-32
    11/32"15/64"MS21046C08NASM2104610000000000000
    10-32
    3/8"15/64"MS21046C3NASM21046100000000000000
    1/4"-28
    7/16"9/32"MS21046C4NASM21046100000000000000
    3/8"-24
    9/16"25/64"MS21046C6NASM21046100000000000000
     
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