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    12 Products

    Mil. Spec. Flex-Top Locknuts for Heavy Vibration

    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.
    Steel
    These locknuts have equivalent strength to Grade 8 and Class 10 steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Cadmium-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.
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    4-40
    		1/4"5/32"MS21045-045000000000000000
    6-32
    		5/16"3/16"MS21045-0650000000000000
    8-32
    		11/32"1/4"MS21045-08500000000000000
    10-32
    		3/8"1/4"MS21045-350000000000000
    1/4"-28
    		7/16"5/16"MS21045-4500000000000000
    5/16"-24
    		1/2"23/64"MS21045-5500000000000000
    3/8"-24
    		9/16"15/32"MS21045-6500000000000000
    7/16"-20
    		11/16"15/32"MS21045-7100000000000000
    1/2"-20
    		3/4"39/64"MS21045-8100000000000000
    9/16"-18
    		7/8"11/16"MS21045-9100000000000000
    5/8"-18
    		15/16"49/64"MS21045-10100000000000000
    3/4"-16
    		1 1/16"57/64"MS21045-12100000000000000
     
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