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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. Prongless. Bottom orientation. Threaded Inserts. Helical Threaded Inserts, Prongless.

    Prongless

    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.
    Prongless—Without a prong to break off and retrieve, these inserts save time and avoid leftover debris in holes.
    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
    Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Prongless
     
    18-8 Stainless Steel
    4-40
    		0.336"31 Ga.
    		0.120"NAS1130-04-301091990A5220000091709A10100000091709A40700000091049A6040000000
     
    Extraction Tools
    Remove installed helical inserts.
    For Prongless Helical Inserts—Remove prongless inserts without damaging threads or the surface of your material. These tools also back out or adjust inserts that are installed too deep.
    For Thread
    Size
    Each
    For Prongless Helical Inserts
    4-40
    		91049A6340000000
     
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