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    52 Products

    Helical Threaded Inserts

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

    Pronged

    Prongless

    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.
    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
    Prong
    Break-Off Tools
    Inserts with
    Installation Tools
    Thread Size
    Installed
    Lg., mm
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Each
    No. of Inserts
    Included
    Each
    Pronged
     
    18-8 Stainless Steel
    M12 x 1.25 mm1231/64"
    		0.484"DIN 8140, SAE MA3279-1121000000000000000000000000000000000000000000000000000000000000000000000000000000————0
    M12 x 1.25 mm1831/64"
    		0.484"DIN 8140, SAE MA3279-16250000000000000000000000000000000000000000000000000000000000000000000000005000000000000000
    M12 x 1.25 mm2431/64"
    		0.484"DIN 8140, SAE MA3279-212100000000000000000000000000000000000000000000000000000000000000000000000000————0
    M12 x 1.5 mm1212.5 mm
    		12.5 mmSAE MA3279-113100000000000000000000000000000000000000000000000000000000000000000000000————0
    M12 x 1.5 mm1812.5 mm
    		12.5 mmDIN 8140, SAE MA3279-163500000000000000000000000000000000000000000000000000000000000000000000000500000000000000
    M12 x 1.5 mm2412.5 mm
    		12.5 mmSAE MA3279-213500000000000000000000000000000000000000000000000000000000000000000000000————0
    M12 x 1.5 mm3012.5 mm
    		12.5 mmSAE MA3279-263100000000000000000000000000000000000000000000000000000000000000000000000————0
    M12 x 1.75 mm1212.5 mm
    		12.5 mmDIN 8140, SAE MA3279-1141000000000000000000000000000000000000000000000000000000000000000000000000————0
    M12 x 1.75 mm1812.5 mm
    		12.5 mmDIN 8140, SAE MA3279-164500000000000000000000000000000000000000000000000000000000000000000000000500000000000000
    M12 x 1.75 mm2412.5 mm
    		12.5 mmDIN 8140, SAE MA3279-214500000000000000000000000000000000000000000000000000000000000000000000000————0
    M12 x 1.75 mm3012.5 mm
    		12.5 mmDIN 8140, SAE MA3279-264500000000000000000000000000000000000000000000000000000000000000000000000————0
     
    Prongless
     
    18-8 Stainless Steel
    M12 x 1.75 mm1212.5 mm
    		12.5 mmNA0276M12-10500000000000000000000000000000000000000000000000000000000———0————0
    M12 x 1.75 mm1812.5 mm
    		12.5 mmNA0276M12-15500000000000000000000000000000000000000000000000000000000———0————0
    M12 x 1.75 mm2412.5 mm
    		12.5 mmNA0276M12-20500000000000000000000000000000000000000000000000000000000———0————0
     
    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 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 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
    		000000000000000
     
    For Prongless Helical Inserts
    M12
    		000000000000000
     

    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
    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
    		—000000000000000
    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, 9/16"-12, 9/16"-18, 5/8"-11, 5/8"-18, 3/4"-10, 3/4"-16, 7/8"-9, 7/8"-14, 1"-8, 1"-12, 1"-14, M4, M5, M6, M7, M8, M9, M10, M12, M13, M14, M15, M16, M18, M20, M22, M24
    		—00000000000000
     
    Narrow Profile
    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
    		Heli-Coil00000000000000
     

    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
    M12
    		1 21/32"3 19/32"Metric
    		431/64"
    		0.4844"Square0000000000000000000000000000000
    M12
    		1 21/32"3 19/32"Metric
    		412.5 mm
    		0.4921"Square0000000000000000000000000000
    M12
    		1 21/32"3 19/32"Metric
    		412.5 mm
    		0.4921"Square0000000000000000000000000000
     

    Helical Threaded Inserts with Installation Tools

    Image of Product. Drill Bit, Installation Tool and Through-Hole Tap. Front orientation. Threaded Inserts. Helical Threaded Inserts with Installation Tools, Pronged, Installation Tool, Through-Hole Tap, Drill Bit.

    Drill Bit, Installation Tool

    and Through-Hole Tap

    Quickly restore stripped threads—these inserts come with through-hole taps and installation tools.
    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.
    Thread Size
    Installed
    Lg., mm
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Inserts
    Included
    Includes
    Each
    Pronged
     
    18-8 Stainless Steel
    M12 x 1.25 mm1812.25 mm
    		0.484"5Drill Bit
    Installation Tool
    Through-Hole Tap    		000000000000000
    M12 x 1.5 mm1812.25 mm
    		0.484"5Drill Bit
    Installation Tool
    Through-Hole Tap    		00000000000000
    M12 x 1.75 mm1831/64"
    		0.484"5Drill Bit
    Installation Tool
    Through-Hole Tap    		00000000000000
     

    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
    Metric Thread
    M12 × 1.25 mm—CrankThreadedHelical Inserts, Screw-Locking Helical Inserts00000000000000
    M12 × 1.25 mmHeli-CoilCrankThreadedHelical Inserts, Screw-Locking Helical Inserts000000000000000
    M12 × 1.5 mm—CrankThreadedHelical Inserts, Screw-Locking Helical Inserts0000000000000
    M12 × 1.5 mmHeli-CoilCrankThreadedHelical Inserts, Screw-Locking Helical Inserts000000000000000
    M12 × 1.75 mm—CrankThreadedHelical Inserts, Screw-Locking Helical Inserts0000000000000
    M12 × 1.75 mmHeli-CoilCrankThreadedHelical Inserts, Screw-Locking Helical Inserts000000000000000
     

    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
    18Drill Bit
    Installation Tool
    M12×1.75 mm Thread × 12 mm Installed Lg. (6 Each)
    M12×1.75 mm Thread × 18 mm Installed Lg. (6 Each)
    M12×1.75 mm Thread × 24 mm Installed Lg. (6 Each)
    Prong Break-Off Tool
    Through-Hole Tap    		Coarse
    		31/64"
    		0.484"000000000000000
    18Drill Bit
    Installation Tool
    M12×1.25 mm Thread × 12 mm Installed Lg. (6 Each)
    M12×1.25 mm Thread × 18 mm Installed Lg. (6 Each)
    M12×1.25 mm Thread × 24 mm Installed Lg. (6 Each)
    Prong Break-Off Tool
    Through-Hole Tap    		Extra Fine
    		31/64"
    		0.484"00000000000000
     

    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
    M12
    		Heli-Coil0000000000000000
     
    For Long Inserts
    1/2"-13, 1/2"-20, M12—000000000000000
     

    Lubricant-Free Seize-Resistant Helical Threaded Inserts

    Image of Product. Front orientation. Threaded Inserts. Lubricant-Free Seize-Resistant Helical Threaded Inserts.
    No lubricant means no mess or particles to contaminate environments such as clean rooms and labs. These inserts are made of Nitronic 60 stainless steel, which prevents sticking or binding that wears out the threads. They're ideal for parts that require frequent disassembly for inspection or repair. 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.
    Inserts
    Through-Hole
    Taps
    Closed-End
    Hole Taps
    Installation
    Tools
    Prong
    Break-Off Tools
    Thread Size
    Installed
    Lg., mm
    Drill Bit
    Size, mm
    For Max.
    Hole Dia., mm
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Each
    Pronged
     
    Nitronic 60 Stainless Steel
    M12 x 1.75 mm1812.5
    		12.510000000000000000000000000000000000000000000000000000000000000000000000000000
     

    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., mm
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Each
    Pronged
     
    18-8 Stainless Steel
    M12 x 1.25 mm1231/64"
    		0.484"SAE MA3329-112500000000000000000000000000000000000000000000000000000000000000000000000000000
    M12 x 1.25 mm1831/64"
    		0.484"DIN 8140, SAE MA3329-1631000000000000000000000000000000000000000000000000000000000000000000000000
    M12 x 1.25 mm2431/64"
    		0.484"SAE MA3329-2121000000000000000000000000000000000000000000000000000000000000000000000000
    M12 x 1.5 mm1812.5 mm
    		12.5 mmDIN 8140, SAE MA3329-162100000000000000000000000000000000000000000000000000000000000000000000000
    M12 x 1.75 mm1212.5 mm
    		12.5 mmDIN 8140, SAE MA3329-114500000000000000000000000000000000000000000000000000000000000000000000000
    M12 x 1.75 mm1812.5 mm
    		12.5 mmDIN 8140, SAE MA3329-164500000000000000000000000000000000000000000000000000000000000000000000000
    M12 x 1.75 mm2412.5 mm
    		12.5 mmDIN 8140, SAE MA3329-214100000000000000000000000000000000000000000000000000000000000000000000000
    M12 x 1.75 mm3012.5 mm
    		12.5 mmDIN 8140, SAE MA3329-264100000000000000000000000000000000000000000000000000000000000000000000000
     

    Prongless Helical Threaded Insert Removal Tools

    Image of Product. Front orientation. Threaded Insert Removal Tools. Prongless Helical Threaded Insert Removal Tools.
    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.
    Replacement Tips—Replacement tips (sold separately) come with one removal tip, two pins, and two springs.
    Removal Tools
    Replacement Tips
    For Thread
    Size
    For Use With
    Each
    Each
    Metric Thread
    M12
    		Helical Inserts, Screw-Locking Helical Inserts00000000000000000000000000000000
     

    Easy-Start Prongless Helical Threaded Insert Installation Tools

    Image of Product. Front orientation. Threaded Insert Installation Tools. Easy-Start Prongless Helical Threaded Insert Installation Tools.
    Install prongless (tangless) helical inserts more quickly and consistently than with standard tools. These tools compress your insert’s diameter and align each coil with the thread pitch, guiding it straight 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 an insert onto these tools and drive them a quarter- to half-turn below the material’s surface. Also known as prewinders.
    For Thread
    Size
    Handle
    Style
    For Use With
    Each
    Metric Thread
    M12 × 1.75 mmCrankHelical Inserts, Screw-Locking Helical Inserts0000000000000000
     
    Replacement Tips
    Replacement tips (sold separately) come with one installation tip, two pins, and two springs. Tip for 10-32 internal thread size does not require springs and pins.
    For Thread
    Size
    Each
    M12
    		000000000000000

    Helical Threaded Insert Installation Tools

    Image of Product. No Handle. Front orientation. Threaded Insert Installation Tools. Helical Threaded Insert Installation Tools.

    No Handle

    Install your pronged helical inserts into tapped holes. Screw an insert onto these tools and drive them a quarter to half-turn below the material’s surface.
    Square Shank—These tools don’t have a handle. Attach them to a tap wrench to turn.
    For Thread
    Size
    Shank
    Type
    For Use With
    Each
    Metric Thread
    M12 × 1.25 mmSquareHelical Inserts, Screw-Locking Helical Inserts000000000000000
    M12 × 1.5 mmSquareHelical Inserts, Screw-Locking Helical Inserts00000000000000
    M12 × 1.75 mmSquareHelical Inserts, Screw-Locking Helical Inserts00000000000000
     
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