McMaster-Carr logo
    Filter by
    Military Specification
    System of Measurement
    Thread Size
    Industrial Info Snippet
    Helical Insert Type
    Installed Length
    Attribute Image
    For Tap Type
    Thread Type
    Thread Direction
    Drill Bit Size
    Attribute Image
    Thread Spacing
    Industrial Info Snippet
    DFARS Specialty Metals
    Industrial Info Compare
    For Material Thickness
    Hole Diameter
    Profile
    Sold As
    U.S.–Mexico–Canada Agreement (USMCA) Qualifying
    Export Control Classification Number (ECCN)
    Industrial Info Snippet
    Tensile Strength
    Industrial Info Snippet
    Passivation
    Forward
    Enter e-mail addresses in the fields below
    Message
    Cancel
    Print
    How can we improve?
    Comments
    E-mail address (if you would like a response)
    8 Products
    About Threaded Inserts
    industrial info icon

    Choose the right threaded insert for your application and learn how to install it securely.

    Helical Threaded Inserts

    Image of Product. Pronged. Bottom orientation. Threaded Inserts. Helical Threaded Inserts, Pronged.

    Pronged

    Restore, reinforce, or create threads in metal. The tough coils on these inserts expand once installed to anchor in a tapped hole. Also known as Heli-Coil inserts, they're often used in engine heads and machinery housings where strong connections are critical. Unlike threadlocking inserts, you can remove and reuse them without them losing their strength.
    Installation requires a drill bit, a helical insert tap, and an installation tool.
    Pronged—The prong attaches to an installation tool for precise control as you drive inserts in. Remove the prong with a punch or break-off tool before inserting a screw.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Through-Hole
    Taps
    Closed-End
    Hole Taps
    Installation
    Tools
    Prong
    Break-Off Tools
    Inserts with
    Installation Tools
    Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Each
    No. of Inserts
    Included
    Each
    Pronged
     
    18-8 Stainless Steel
    4-40
    		0.112"31 Ga.
    		0.120"MS1220761091732A3510000091709A10100000091709A40700000090261A151000000092955A10300000001098356A1140000000
     
    Extraction Tools
    Remove installed helical inserts.
    For Pronged Helical Inserts—Place the tip into pronged inserts and lightly strike the tool’s head. Then, turn the tool counterclockwise with pressure to extract the insert.
    For Thread Size
    Each
    For Pronged Helical Inserts
    3-48, 3-56, 4-40, 4-48, 5-40, 5-44, 6-32, 6-40, 8-32, 8-36, 8-40, M2.5, M3, M3.5, M4
    		90254A310000000
     

    Seize-Resistant Helical Threaded Inserts

    Image of Product. Pronged. Bottom orientation. Threaded Inserts. Seize-Resistant Helical Threaded Inserts, Pronged.

    Pronged

    Install and remove screws repeatedly without sticking or binding. These inserts have a dry-film lubricant on their surface for smooth installation. They're ideal for parts that require frequent disassembly for inspection or repair. Also known as Heli-Coil inserts.
    Installation requires a drill bit, a helical insert tap, and an installation tool.
    Pronged—The prong attaches to an installation tool for precise control as you drive inserts in. Remove the prong with a punch or break-off tool before inserting a screw.
    Dry-Film-Lubricated 18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Through-Hole
    Taps
    Closed-End
    Hole Taps
    Installation
    Tools
    Prong
    Break-Off Tools
    Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Each
    Pronged
     
    Dry-Film-Lubricated 18-8 Stainless Steel
    4-40
    		0.112"31 Ga.
    		0.120"MIL-I-8846, MS122076191000A1210000091709A10100000091709A40700000090261A151000000092955A1030000000
     
    back to top