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    5 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.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Inserts
    Through-Hole
    Taps
    Closed-End
    Hole Taps
    Installation
    Tools
    Thread Size
    Installed
    Lg., mm
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Pronged
     
    18-8 Stainless Steel
    M16 x 1.5 mm2421/32"
    		0.656"SAE MA3279-167692450A61900000092450A621000000092450A622000000092450A6110000000
     
    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
    7/16"-14, 7/16"-20, 1/2"-13, 1/2"-20, 1/2"-28, 9/16"-12, 9/16"-18, 5/8"-11, 5/8"-18, 5/8"-24, 3/4"-10, 3/4"-16, 3/4"-20, 7/8"-9, 7/8"-14, 7/8"-20, 1"-8, 1"-12, 1"-14, M12, M14, M16, M18, M20, M22, M24
    		90254A330000000
     
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