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    Top-Lock Distorted-Thread Locknut

    Zinc-Flake Coated High-Strength Grade C Steel, 7/16"-20

    Image of Product. Bottom orientation. Top-Lock Distorted-Thread Locknut, Zinc-Flake Coated High-Strength Grade C Steel, 7/16"-20.
    Technical Drawing of Top-Lock Distorted-Thread Locknut, Zinc-Flake Coated High-Strength Grade C Steel, 7/16"-20.
    Image of Product. Bottom orientation. Top-Lock Distorted-Thread Locknut, Zinc-Flake Coated High-Strength Grade C Steel, 7/16"-20.
    Image of Product. Side1 orientation. Contains SizingReference. Top-Lock Distorted-Thread Locknut, Zinc-Flake Coated High-Strength Grade C Steel, 7/16"-20.
    2-D PDF
    000000 per pack of 5
    99291A690
    In stock
    99291A690
    000000 per pack of 5
    Pack of 5
    In stock
    Streamline your design process with our Solidworks Add-In
    Available for Solidworks 2017 or newer.
    Thread Direction

    Right Hand

    Hex Nut Profile

    Standard

    Distorted Thread Type

    Top Lock

    Locking Type

    Distorted Thread

    Fastener Strength Rating

    High

    Finished Material

    Zinc-Flake-Coated Steel

    Thread Size

    7/16"-20

    Width

    11/16"

    Height

    3/8"

    Fastener Strength Grade/Class

    ASTM Grade C

    Drive Style

    External Hex

    Nut Type

    Hex, Locknut

    Performance

    Vibration Resistant, High Strength

    System of Measurement

    Inch

    Thread Fit

    Unified Standard Class 2B

    Thread Spacing

    Fine

    Thread Type

    UNF

    Country of Origin

    Taiwan

    DFARS Compliance

    Not Specialty Metals Compliant

    Export Control Classification Number (ECCN)

    EAR99

    REACH Compliance

    REACH (EC 1907/2006) (01/21/2025, 247 SVHC) Compliant

    RoHS Compliance

    RoHS 3 (2015/863/EU) Compliant

    Schedule B Number

    731816.0000

    U.S.–Mexico–Canada Agreement (USMCA) Qualifying

    No

    Irregularly shaped threads at the top of these locknuts grip the screw for a stronger hold than nylon-insert locknuts. Although the threads prevent the nut from backing out due to vibration, 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. Nuts are not reusable.

    High-Strength SteelRated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.

    Zinc-Flake-Coated SteelThe most durable zinc coating, this multilayer finish resists wear for long-term rust protection. However, similar to zinc-yellow-chromate plating, it won't hold up to harsh chemicals like stainless steel can.

    The information in this 3-D model is provided for reference only.