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    17 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.
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Prongless
     
    18-8 Stainless Steel
    0-80
    		0.060"52 Ga.
    		0.064"591990A5010000091709A68100000091709A68200000091049A1030000000
    0-80
    		0.090"52 Ga.
    		0.064"591990A502000091709A6810000091709A6820000091049A103000000
    0-80
    		0.120"52 Ga.
    		0.064"591990A503000091709A6810000091709A6820000091049A103000000
     
    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
    0-80
    		91049A3760000000
     

    Screw-to-Expand Press-In Threaded Inserts for Plastic

    Image of Product. Bottom orientation. Threaded Inserts. Screw-to-Expand Press-In Threaded Inserts for Plastic, Standard Profile.

    Standard

    Profile

    Press these inserts into a drilled hole, then install a screw to expand them. Inserts won't lose their strength as you remove and reinsert screws during inspection or repair. The sharp diamond knurls dig into the surrounding material for a stronger hold than other press-in inserts for plastic. Install inserts with an arbor press or similar pressure tool.
    Brass—Conductive and nonmagnetic, these inserts are useful for electrical applications. They resist moisture but aren't as strong as steel inserts.
    Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Pkg.
    Qty.
    Pkg.
    Standard Profile
     
    Brass
    0-80
    		0.125"3/32"
    		0.094"2592395A10900000
     

    Key-Locking Threaded Inserts for Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Key-Locking Threaded Inserts for Soft Metal.
    Add strong threads in soft metal, such as aluminum. The keys on these inserts drive into holes to hold more securely than thread-locking or helical inserts. They prevent slipping and rotating, so they’re stable enough for use in vehicle or aerospace parts that experience heavy vibration. These inserts are comparable to Keensert inserts.
    To install, drill and tap a hole in your material. Then, thread the insert onto the installation tool and screw it into the hole. Place the tool over the keys and hit it with a hammer to drive them in.
    Thin Wall—Use these inserts near the edge of workpieces or wherever you only have space for a small hole. They're also lighter than standard and extra-thick wall inserts for applications with strict weight limitations.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Installation
    Tools
    Each
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    1-9
    10-Up
    Each
    Thin Wall
     
    18-8 Stainless Steel
    0-80
    		6-40
    		0.109"31 Ga.
    		0.120"293340A9010000000000006721N11000000
     

    Key-Locking Threaded Insert Installation Tools

    Image of Product. Front orientation. Threaded Insert Installation Tools. Key-Locking Threaded Insert Installation Tools, Style C.

    Style C

    Thread inserts and drive down their keys with a single tool. These tools are compatible with Keensert inserts.
    Threaded Insert Installation Tools with Spring
    Image of Product. Front orientation. Threaded Insert Installation Tools. Key-Locking Threaded Insert Installation Tools, Style C.

    Style C

    The tradespersons’ choice for installing Mil. Spec. inserts. A spring holds the sleeve under tension, so wobbles and jostles don’t interfere with a clean, professional install.
    For Thread
    Size
    For Tap Thread
    Size
    Style
    Features
    Each
    For Thin-Wall Inserts
    0-80
    		6-40
    		CSleeve, Threaded Tip6721N11000000
     

    Mold-In Threaded Inserts for Plastic

    Image of Product. Bottom orientation. Threaded Inserts. Mold-In Threaded Inserts for Plastic.
    Mold the strongest metal threads into plastic parts. Designed for injection molding, these inserts become inseparable from your part. They form a stronger bond than heat-set and press-fit inserts and are better for frequent use than threads cut directly into material. Unlike heat-set inserts, they can be used in a wide variety of plastics, including thermoset plastics that can’t be reformed.
    To install, position these inserts in your mold cavity with a core pin (not included).
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals. Since they’re lead-free, they can be safely recycled.
    Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    For Core
    Pin Dia.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    0-80
    		0.125"48 Ga.
    		0.078"0.050"107588N9900000
     

    Prongless Helical Threaded Insert Installation Tools

    Image of Product. Front orientation. Threaded Insert Installation Tools. Prongless Helical Threaded Insert Installation Tools.
    These tools install prongless helical inserts, also known as tangless inserts. Screw the insert onto your installation tool and drive it between a quarter-turn and half-turn below the surface.
    For Thread
    Size
    Handle
    Style
    For Use With
    Each
    Standard (UN) Thread
    0-80
    		StraightHelical Inserts, Screw-Locking Helical Inserts91049A1030000000
     
    Replacement Tips
    Replacement installation tool tips (sold separately) include one installation tip, two pins, and two springs.
    For Thread
    Size
    Each
    0-80
    		91049A201000000

    Tapered Heat-Set Threaded Inserts For Plastic

    Image of Product. Front orientation. Threaded Inserts. Tapered Heat-Set Threaded Inserts For Plastic.
    Tapered at one end, these inserts are easier to align in a hole during installation than straight inserts. Use a drill bit to create a straight hole, then taper the top half. Once installed, heat the insert with a soldering tip to melt the surrounding plastic.
    Brass—Conductive and nonmagnetic, these inserts are useful for electrical applications. They resist moisture but aren't as strong as steel inserts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals. Since they’re lead-free, they can be safely recycled.
    Inserts
    Soldering
    Installation Tips
    Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size, mm
    For Max.
    Hole Dia.
    For Hole
    Taper Angle
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Each
    Brass
    0-80
    		0.115"3
    		3 mm8°ASTM B1610093365A10200000092160A341000000
    0-80
    		0.188"36 Ga.
    		0.107"8°ASTM B165093365A2200000092160A34100000
     
    18-8 Stainless Steel
    0-80
    		0.115"32 Ga.
    		0.118"8°ASTM A582197163A101000092160A34100000
     
    Soldering Irons
    Each
    Economy Soldering Iron, 60W7662A696000000
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