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    20 Products
    About Threaded Inserts
    industrial info icon

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

    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
    2-56
    6-40
    0.109"31 Ga.
    0.120"293340A902000000000093904A71100000
     

    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
    Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Each
    Pronged
     
    18-8 Stainless Steel
    6-40
    0.138"25 Ga.
    0.150"MS1246531091732A0120000091709A06300000091709A41900000090261A106000000092955A105000000
    6-40
    0.207"25 Ga.
    0.150"MS1246931091732A014000091709A0630000091709A4190000090261A10600000092955A10500000
    6-40
    0.276"25 Ga.
    0.150"MS1247331091732A710000091709A0630000091709A4190000090261A10600000092955A10500000
     
    Extraction Tools

    Screw-Locking Helical Threaded Inserts

    Image of Product. Pronged. Bottom orientation. Threaded Inserts. Screw-Locking Helical Threaded Inserts, Pronged.

    Pronged

    The irregularly shaped threads tightly grip screws to prevent them from loosening or backing out under vibration. Use these inserts to create or repair threads in pumps and other machinery that shakes and rattles. 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.
    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
     
    18-8 Stainless Steel
    6-40
    0.138"25 Ga.
    0.150"NASM21209, MS21209F06101090296A0240000091709A06300000091709A41900000090261A106000000092955A105000000
    6-40
    0.207"25 Ga.
    0.150"NASM21209, MS21209F0615590296A189000091709A0630000091709A4190000090261A10600000092955A10500000
    6-40
    0.276"25 Ga.
    0.150"NASM21209, MS21209F0620590296A190000091709A0630000091709A4190000090261A10600000092955A10500000
     

    Helical Threaded Insert Assortments with Installation Tools

    Image of Product. Front orientation. Threaded Inserts. Helical Threaded Insert Assortments with Installation Tools.
    Repair damaged threads or create new ones. These convenient assortments include helical inserts, an installation tool for each thread size, a drill bit, and a tap. The inserts are also known as Heli-Coil inserts.
    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.
    No. of Inserts
    Included
    Includes
    Thread
    Spacing
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Each
    Pronged
     
    18-8 Stainless Steel
    366-40 Thread × 0.138" Installed Lg. (12 Each)
    6-40 Thread × 0.207" Installed Lg. (12 Each)
    6-40 Thread × 0.276" Installed Lg. (12 Each)
    Drill Bit
    Installation Tool
    Prong Break-Off Tool
    Through-Hole Tap
    Fine
    25 Ga.
    0.150"91732A9070000000
     

    Screw-Locking Seize-Resistant Key-Locking Threaded Inserts for Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Screw-Locking Seize-Resistant Key-Locking Threaded Inserts for Soft Metal.
    Create the tightest hold in aluminum and other soft metal without screws sticking. The lubricant on these inserts eases installation, and the irregularly shaped threads won’t let screws back out from vibration. Inserts have keys that drive into material to prevent them from slipping or rotating in the hole.
    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.
    Dry-Film-Lubricated 18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Installation
    Tools
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    Each
    Each
    Thin Wall
     
    Dry-Film-Lubricated 18-8 Stainless Steel
    2-56
    6-40
    0.109"31 Ga.
    0.118"297255A11200000093904A711000000
     

    Seize-Resistant Swage-Locking Threaded Inserts

    Image of Product. Bottom orientation. Threaded Inserts. Seize-Resistant Swage-Locking Threaded Inserts.
    Image of Specification. Front orientation. Contains Annotated. Threaded Inserts. Seize-Resistant Swage-Locking Threaded Inserts.
    Smoothly install these inserts for strong threads near the edges and corners of soft metal surfaces. They’re lubricated to prevent sticking as you thread them in. Since these have thinner walls than our key-locking and thread-locking inserts, they don’t need as much space and won't bulge or crack the material. The knurls press (swage) into the material to keep inserts in place when you tighten or loosen a screw.
    To install these inserts, you need a drill bit, a counterbore, a standard tap, an installation tool, and a hammer. Drill a hole, counterbore the top, and tap it. Place the insert into the installation tool, then hand-tighten it into the tapped hole. Strike the tool to secure the insert and drive the knurls into the surrounding material.
    High-Strength Dry-Film-Lubricated Cadmium-Plated Alloy Steel—Stronger than our 17-4 PH stainless steel inserts, these inserts absorb impact without cracking and stand up to high-pressure applications. The cadmium plating prevents corrosion in wet environments.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Inserts
    Installation
    Tools
    For
    Counterbore
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    For Max.
    Hole Dia.
    Dia.
    Dp.
    Mil. Spec.
    Each
    Each
    High-Strength Dry-Film-Lubricated Cadmium-Plated Alloy Steel
    2-56
    6-40
    0.141"0.113"0.138"0.045"MIL-DTL-45932/193572A101000006645N1010000000
     

    Swage-Locking Threaded Inserts

    Image of Product. Bottom orientation. Threaded Inserts. Swage-Locking Threaded Inserts.
    Image of Specification. Front orientation. Contains Annotated. Threaded Inserts. Swage-Locking Threaded Inserts.
    Add strong threads to the edges of soft metal without bulging or cracking the material. These inserts have thinner walls than our key-locking and thread-locking inserts, so they don’t need as much space around them. The knurls press (swage) into the material to keep inserts in place when you tighten or loosen a screw.
    To install these inserts, you need a drill bit, a counterbore, a standard tap, an installation tool, and a hammer. Drill a hole, counterbore the top, and tap it. Place the insert into the installation tool, then hand-tighten it into the tapped hole. Strike the tool to secure the insert and drive the knurls into the surrounding material.
    High-Strength 17-4 PH Stainless Steel—The strongest stainless steel inserts we offer. They handle high-stress installations, such as pump and compressor housings, and the heavy vibration of aircraft parts. They won’t rust in wet and outdoor environments but can’t withstand the harsh chemicals and acids that 316 stainless steel can.
    Inserts
    Installation
    Tools
    For
    Counterbore
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    For Max.
    Hole Dia.
    Dia.
    Dp.
    Mil. Spec.
    Each
    Each
    High-Strength 17-4 PH Stainless Steel
    2-56
    6-40
    0.141"0.113"0.138"0.045"MIL-DTL-45932/193570A1010000006645N1010000000
     
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