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    Black-Oxide Alloy Steel Socket Head Screw

    1/4"-20 Thread Size, 3/4" Long

    Image of Product. Front orientation. Black-Oxide Alloy Steel Socket Head Screw, 1/4"-20 Thread Size, 3/4" Long.
    Technical Drawing of Black-Oxide Alloy Steel Socket Head Screw, 1/4"-20 Thread Size, 3/4" Long.
    Image of Product. Back orientation. Black-Oxide Alloy Steel Socket Head Screw, 1/4"-20 Thread Size, 3/4" Long.
    Image of Product. Side1 orientation. Contains SizingReference. Black-Oxide Alloy Steel Socket Head Screw, 1/4"-20 Thread Size, 3/4" Long.
    2-D PDF
    $11.38 per pack of 50
    91251A540
    In stock
    91251A540
    $11.38 per pack of 50
    Pack of 50
    In stock
    Streamline your design process with our Solidworks Add-In
    Available for Solidworks 2017 or newer.
    Thread

    Size

    1/4"-20

    Spacing

    Coarse

    Type

    UNRC

    Fit

    Unified Standard Class 3A

    Direction

    Right Hand

    Socket Head Profile

    Standard

    Fastener Head Type

    Socket

    Drive Style

    Hex

    Length

    3/4"

    Head

    Diameter

    3/8"

    Height

    1/4"

    Threading

    Fully Threaded

    Tensile Strength

    170,000 psi

    Specifications Met

    ASTM A574

    Certificate Form

    Digital

    Certificate Type

    Material Certificate with Traceable Lot Number

    Drive Size

    3/16"

    Hardness

    Rockwell C37

    Material

    Black-Oxide Alloy Steel

    Performance

    High Strength

    Screw Size Decimal Equivalent

    0.25"

    System of Measurement

    Inch

    Tip Type

    Flat

    Country of Origin

    United States

    DFARS Compliance

    Specialty Metals Compliant (252.225-7009)

    Export Control Classification Number (ECCN)

    EAR99

    REACH Compliance

    REACH (EC 1907/2006) (02/04/2026, 253 SVHC) Compliant

    RoHS Compliance

    RoHS 3 (2015/863/EU) Compliant

    Schedule B Number

    731815.9000

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

    Yes

    Made of alloy steel, these screws are the standard for high-strength fastening. Use them in high-load applications such as dies, presses, and heavy equipment. The deep, six-point socket keeps the hex key from slipping out and damaging the drive.

    Length is measured from under the head.

    Black-Oxide Alloy Steel—Typically chosen for their appearance, these screws have a dark, matte coating to create a finished look. They offer minimal corrosion resistance, so they're best for dry environments.

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