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    29 Products

    Mil. Spec. Thin-Profile Nylon-Insert Locknuts

    These locknuts are manufactured and tested to strict U.S. military standards for material and construction. They are about half the height of standard-profile locknuts to fit in spaces with low clearance. You can also use them as jam nuts by threading them against a hex nut to hold it in place. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Low-Strength Steel
    Image of Product. Front orientation. Locknuts. Mil. Spec. Thin-Profile Nylon-Insert 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.
    Cadmium Yellow-Chromate-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc-yellow-chromate plating.
    Thread
    Size
    Wd.
    Ht.
    Mil.
    Spec.
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    4-40
    1/4"1/8"MS21083N04250NASM210831095496A310000000
    6-32
    5/16"9/64"MS21083N06250NASM210831095496A32000000
    8-32
    11/32"3/16"MS21083N08250NASM210831095496A3300000
    10-32
    3/8"3/16"MS21083N3250NASM210831095496A3400000
    1/4"-28
    7/16"7/32"MS21083N4250NASM210831095496A3500000
    1/2"-20
    3/4"5/16"MS21083N8250NASM21083195496A3800000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Locknuts. Mil. Spec. Thin-Profile Nylon-Insert Locknuts.
    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.
    Ht.
    Mil.
    Spec.
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    2-56
    1/4"7/64"MS21083C02250NASM21083597231A480000000
    4-40
    1/4"1/8"MS21083C04250NASM210831097231A41000000
    6-32
    5/16"9/64"MS21083C06250NASM210831097231A42000000
    8-32
    11/32"3/16"MS21083C08250NASM21083597231A4300000
    10-32
    3/8"3/16"MS21083C3250NASM21083597231A44000000
    1/4"-28
    7/16"7/32"MS21083C4250NASM21083597231A45000000
    5/16"-24
    1/2"17/64"MS21083C5250NASM21083197231A4600000
    3/8"-24
    9/16"9/32"MS21083C6250NASM21083197231A4700000
    7/16"-20
    11/16"21/64"MS21083C7250NASM21083197231A51000000
    1/2"-20
    3/4"5/16"MS21083C8250NASM21083197231A4900000
    5/8"-18
    15/16"13/32"MS21083C10250NASM21083197231A52000000
     

    Mil. Spec. Thin-Profile Hex Nuts

    These nuts are manufactured and tested to strict U.S. military standards for material and construction. About half the height of standard-profile nuts, they fit in spaces with low clearance. You can also use them as jam nuts by threading them against another hex nut to hold it in place.
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Hex Nuts. Mil. Spec. Thin-Profile Hex 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.
    Thread
    Size
    Wd.
    Ht.
    Mil.
    Spec.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1/4"-20
    7/16"5/32"MS35691-3Fed. Spec. FF-N-836
    592101A210000000
    1/4"-28
    7/16"5/32"MS35691-7Fed. Spec. FF-N-836
    192101A3200000
    5/16"-18
    1/2"3/16"MS35691-11Fed. Spec. FF-N-836
    592101A43000000
    5/16"-24
    1/2"3/16"MS35691-15Fed. Spec. FF-N-836
    592101A54000000
    3/8"-16
    9/16"7/32"MS35691-19Fed. Spec. FF-N-836
    192101A6500000
    3/8"-24
    9/16"7/32"MS35691-23Fed. Spec. FF-N-836
    192101A7600000
    7/16"-14
    11/16"1/4"MS35691-27Fed. Spec. FF-N-836
    192101A1010000
    7/16"-20
    11/16"1/4"MS35691-31Fed. Spec. FF-N-836
    192101A1020000
    1/2"-13
    3/4"5/16"MS35691-35Fed. Spec. FF-N-836
    192101A8700000
    1/2"-20
    3/4"5/16"MS35691-39Fed. Spec. FF-N-836
    192101A9800000
    5/8"-11
    15/16"3/8"MS35691-51Fed. Spec. FF-N-836
    192101A10300000
    5/8"-18
    15/16"3/8"MS35691-55Fed. Spec. FF-N-836
    192101A10400000
     
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