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    23 Products
    About Threaded Inserts
    industrial info icon

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

    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.
    Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    For Hole
    Taper Angle
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Brass
    5-40
    		0.150"8 Ga.
    		0.199"8°ASTM B1625000000000000000
    5-40
    		0.250"13 Ga.
    		0.185"8°ASTM B162500000000000000
     
    18-8 Stainless Steel
    5-40
    		0.150"8 Ga.
    		0.199"8°ASTM A5822500000000000000
    5-40
    		0.250"13 Ga.
    		0.185"8°ASTM A5822500000000000000
     

    Spring-Loaded Helical Threaded Insert Prong Break-Off Tools

    Image of Product. Front orientation. Threaded Insert Installation Tools. Spring-Loaded Helical Threaded Insert Prong Break-Off Tools.
    Cleanly snap prongs off installed helical inserts with just one hand. Because they work faster than standard prong break-off tools, these are a good choice when you have many prongs to remove. Press your tool into an insert to trigger the spring-loaded punch and snap off the prong.
    For Standard-Length Inserts—Use these tools for inserts that are 1 to 2 times as long as the diameter.
    For Long Inserts—Use these tools for inserts that are 2 1/2 to 3 times as long as the diameter.
    For Thread Size
    Mfr.
    Each
    For Standard-Length Inserts
    4-40, 4-48, 5-40Heli-Coil0000000000000000
     
    For Long Inserts
    4-40, 4-48, 5-40, M3—00000000000000
     

    Helical Threaded Insert Removal Tools

    Image of Product. Front orientation. Threaded Insert Removal Tools. Helical Threaded Insert Removal Tools.
    To remove installed helical inserts, place the tip of these tools into the insert and lightly strike the tool’s head. Then, turn the tool counterclockwise with pressure to extract the insert.
    Narrow Profile—The tip of these tools has a narrower angle than standard removal tools to reduce the chance it will dig into your material’s surface when you strike the tool.
    For Thread Size
    Mfr.
    Each
    Standard Profile
    2-56, 3-48, 3-56, 4-40, 4-48, 5-40, 6-32, 6-40, 8-32, 8-36, M2, M2.2, M2.5, M3, M3.5, M4
    		—000000000000000
    4-40, 4-48, 5-40, 6-32, 6-40, 8-32, 8-36, 10-24, 10-32, 12-24, 1/4"-20, 1/4"-28, 5/16"-18, 5/16"-24, 3/8"-16, 3/8"-24, 7/16"-14, 7/16"-20, 1/2"-13, 1/2"-20, M3, M3.5, M4, M5, M6, M7, M8, M9, M10, M12, M13, M14
    		—00000000000000
     
    Narrow Profile
    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
    		Heli-Coil00000000000000
     

    Helical Threaded Inserts

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

    Pronged

    Restore, reinforce, or create metal threads. 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. Easy-start installation tools compress the diameter of your insert so it fits easily into a tapped hole. These tools are the best choice for preventing misaligned or damaged threads—just make sure you have space to turn the crank.
    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
    5-40
    		0.125"29 Ga.
    		0.136"MS122077100000000000000000000000000000000000000000000000000000000000000000000000000000
    5-40
    		0.188"29 Ga.
    		0.136"MS1221171000000000000000000000000000000000000000000000000000000000000000000000000
    5-40
    		0.250"29 Ga.
    		0.136"MS1221571000000000000000000000000000000000000000000000000000000000000000000000000
     
    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
    		000000000000000
     

    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 automobile parts 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. Easy-start installation tools compress the diameter of your insert so it fits easily into a tapped hole. These tools are the best choice for preventing misaligned or damaged threads—just make sure you have space to turn the crank.
    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
    5-40
    		0.125"29 Ga.
    		0.136"NASM21209, MS21209C0510100000000000000000000000000000000000000000000000000000000000000000000000000000
    5-40
    		0.188"29 Ga.
    		0.136"NASM21209, MS21209C05151000000000000000000000000000000000000000000000000000000000000000000000000
    5-40
    		0.250"29 Ga.
    		0.136"NASM21209, MS21209C0520500000000000000000000000000000000000000000000000000000000000000000000000
     

    Helical Insert Taps

    Image of Product. Front orientation. Taps. Helical Insert Taps.
    Match the size of helical inserts so they fit tightly when installed in the hole.
    High-Speed Steel—These taps resist heat and wear to stay sharp.
    Plug Chamfer—Our go-to chamfer type. With a longer taper than a bottoming chamfer, they are easier to turn but won't thread as close the bottom of a hole.
    Bottoming Chamfer—Cut all the way to the bottom of blind holes with taps that have the shortest taper. Since these require the most force to turn, they’re often used to finish holes started by taper- or plug-chamfer taps.
    Drill Bit
    Plug Chamfer
    Bottoming
    Chamfer
    For Insert
    Size
    Thread
    Lg.
    Overall
    Lg.
    For Insert
    Thread Type
    No. of
    Flutes
    Size
    Decimal Size
    Equiv.
    Shank
    Type
    Each
    Each
    High-Speed Steel
     
    Uncoated
    5-40
    		3/4"2 1/8"UNC
    		329 Ga.
    		0.136"Square000000000000000000000000000000
     

    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
    365-40 Thread × 0.188" Installed Lg. (12 Each)
    5-40 Thread × 1/4" Installed Lg. (12 Each)
    5-40 Thread × 1/8" Installed Lg. (12 Each)
    Drill Bit
    Installation Tool
    Prong Break-Off Tool
    Through-Hole Tap    		Coarse
    		29 Ga.
    		0.136"0000000000000000
     

    Easy-Start Helical Threaded Insert Installation Tools

    These tools compress the diameter of your insert so it fits easily into a tapped hole. They’re the best choice for preventing misaligned or damaged threads—just make sure you have space to turn the crank. Screw or slide an insert onto your tool and drive it between a quarter-turn and half-turn below the surface. Also known as prewinders.
    Threaded Insert Installation Tools with Depth Stop
    Image of Product. Front orientation. Threaded Insert Installation Tools. Easy-Start Helical Threaded Insert Installation Tools, Threaded Insert Installation Tools with Depth Stop, Crank Handle.
    Image of Specification. Threaded Drive. Front orientation. ZoomedIn view. Threaded Drive Helical Insert Tool. Easy-Start Helical Threaded Insert Installation Tools, Threaded Insert Installation Tools with Depth Stop.

    Crank Handle

    Threaded Drive

    Ensure consistent installation across multiple inserts. Set your desired installation depth, and the stop will prevent you from driving your insert any further.
    Threaded Drive Helical Insert Tool—These tools align each coil of your insert perfectly with the thread pitch of your tapped hole for easy installation.
    For Thread
    Size
    Mfr.
    Handle
    Style
    Helical Insert
    Tool Drive Type
    For Use With
    Each
    Standard (UN) Thread
    5-40
    		—CrankThreadedHelical Inserts, Screw-Locking Helical Inserts0000000000000
    5-40
    		Heli-CoilCrankThreadedHelical Inserts, Screw-Locking Helical Inserts000000000000000
     

    Stainless Steel Socket Nuts

    Image of Product. Front orientation. Socket Nuts. Stainless Steel Socket Nuts.
    These nuts are chemical resistant and may be mildly magnetic. Also known as Allen nuts, use them with socket head cap screws in recessed holes and tight spaces that don't have enough clearance for a wrench. Tighten them with a 6-point hex key. They can also be used as an insert by pressing or drawing them into nonhardened steel, cast iron, or soft nonferrous metal or by molding them into plastic, ceramic, fiber, and similar materials.
    Thread
    Size
    OD
    Ht.
    Threading
    Thread
    Dp.
    For Hole
    Dia.
    Hex Key
    Size
    Each
    18-8 Stainless Steel
    5-40
    		0.19"0.21"Partially Threaded0.1"0.202"1/8"00000000000000
     

    Steel Socket Nuts

    Image of Product. Front orientation. Socket Nuts. Steel Socket Nuts.
    Also known as Allen nuts, use these with socket head cap screws in recessed holes and tight spaces that don't have enough clearance for a wrench. Tighten them with a 6-point hex key. They can also be used as an insert by pressing or drawing them into nonhardened steel, cast iron, or soft nonferrous metal or by molding them into plastic, ceramic, fiber, and similar materials. Made from alloy steel, they're comparable in strength to Grade 9 bolts.
    Thread
    Size
    OD
    Ht.
    Threading
    Thread
    Dp.
    For Hole
    Dia.
    Hex Key
    Size
    Each
    Alloy Steel
    5-40
    		0.18"0.2"Partially Threaded0.1"0.202"1/8"00000000000000
     

    Punch-Style Helical Threaded Insert Prong Break-Off Tools

    Image of Product. Front orientation. Threaded Insert Installation Tools. Punch-Style Helical Threaded Insert Prong Break-Off Tools.
    Break the prong off of installed helical inserts. Place these tools inside the insert and hit the back with a hammer. Once removed, thread in your fastener.
    For Thread Size
    Handle
    Style
    For Use With
    Each
    4-40, 4-48, 5-40, M3StraightHelical Inserts, Screw-Locking Helical Inserts000000000000
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