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    32 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 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.
    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
    M2.5 x 0.45 mm2.537 Ga.
    		0.104"DIN 8140, SAE MA3279-1011091732A7640000091709A67800000091709A57800000090261A187000000092955A2040000000————0
    M2.5 x 0.45 mm3.837 Ga.
    		0.104"DIN 8140, SAE MA3279-1511091732A767000091709A6780000091709A5780000090261A18700000092955A2040000001091732A8730000000
    M2.5 x 0.45 mm537 Ga.
    		0.104"DIN 8140, SAE MA3279-2011091732A770000091709A6780000091709A5780000090261A18700000092955A204000000————0
    M2.5 x 0.45 mm6.337 Ga.
    		0.104"DIN 8140, SAE MA3279-2511091732A771000091709A6780000091709A5780000090261A18700000092955A204000000————0
     
    Prongless
     
    18-8 Stainless Steel
    M2.5 x 0.45 mm2.537 Ga.
    		0.104"NA0276M2A-101091990A401000091709A6780000091709A5780000091049A620000000———0————0
    M2.5 x 0.45 mm3.837 Ga.
    		0.104"NA0276M2A-151091990A404000091709A6780000091709A5780000091049A620000000———0————0
    M2.5 x 0.45 mm537 Ga.
    		0.104"NA0276M2A-201091990A407000091709A6780000091709A5780000091049A620000000———0————0
    M2.5 x 0.45 mm6.337 Ga.
    		0.104"NA0276M2-251091990A554000091709A6780000091709A5780000091049A620000000———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
    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
    		90254A310000000
     
    For Prongless Helical Inserts
    M2.5
    		91049A362000000
     

    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
    M2.5
    		5/8"1 15/16"Metric
    		337 Ga.
    		0.104"Square91709A67800000091709A578000000
     

    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
    		—90254A111000000
     
    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-Coil90254A31000000
     

    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.
    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
    M2.5 x 0.45 mm2.52.65
    		2.65593914A0090000091709A67800000091709A57800000090261A187000000092955A2040000000
    M2.5 x 0.45 mm3.82.65
    		2.65593914A026000091709A6780000091709A5780000090261A18700000092955A204000000
    M2.5 x 0.45 mm52.65
    		2.65593914A0430000091709A6780000091709A5780000090261A18700000092955A204000000
     

    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
    M2.5 × 0.45 mm—CrankThreadedHelical Inserts, Screw-Locking Helical Inserts1338N52000000
    M2.5 × 0.45 mmHeli-CoilCrankThreadedHelical Inserts, Screw-Locking Helical Inserts90261A187000000
     

    Screw-Locking Helical Threaded Inserts

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

    Pronged

    Prongless

    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.
    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
    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
    M2.5 x 0.45 mm2.537 Ga.
    		0.104"DIN 8140, SAE MA3329-1011090296A4010000091709A67800000091709A57800000090261A187000000092955A2040000000
    M2.5 x 0.45 mm3.837 Ga.
    		0.104"DIN 8140, SAE MA3329-1511090296A402000091709A6780000091709A5780000090261A18700000092955A204000000
    M2.5 x 0.45 mm537 Ga.
    		0.104"SAE MA3329-2011090296A403000091709A6780000091709A5780000090261A18700000092955A204000000
     
    Prongless
     
    18-8 Stainless Steel
    M2.5 x 0.45 mm2.537 Ga.
    		0.104"NA0276M2A-L101091630A221000091709A6780000091709A5780000091049A620000000———0
     

    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, Drill Bit, Through-Hole Tap, Installation Tool.

    Drill Bit, Installation Tool

    and Through-Hole Tap

    Quickly restore stripped threads—these inserts come with through-hole taps and installation tools. The tough coils on these inserts expand once installed to anchor in a tapped hole.
    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, mm
    For Max.
    Hole Dia.
    No. of Inserts
    Included
    Includes
    Each
    Pronged
     
    18-8 Stainless Steel
    M2.5 x 0.45 mm3.82.55
    		0.102"10Drill Bit
    Installation Tool
    Through-Hole Tap    		91732A8730000000
     

    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
    M2.5 × 0.45 mmCrankHelical Inserts, Screw-Locking Helical Inserts91049A6200000000
     
    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
    M2.5
    		91049A750000000

    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
    M2.2, M2.5Heli-Coil92955A2040000000
     
    For Long Inserts
    3-48, 3-56, M2.5—92955A41200000
     

    Screw-Locking Seize-Resistant Helical Threaded Inserts

    Image of Product. Bottom orientation. Threaded Inserts. Screw-Locking Seize-Resistant Helical Threaded Inserts.
    Screws won't get stuck or come loose with these inserts. A dry film on the surface lubricates fasteners during insertion to prevent sticking and binding. Once installed, the irregularly shaped threads tightly grip screws to keep them in place under vibration. 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.
    Dry-Film-Lubricated 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
     
    Dry-Film-Lubricated 18-8 Stainless Steel
    M2.5 x 0.45 mm3.837 Ga.
    		0.104"DIN 8140, SAE MA3330-151191000A5020000091709A67800000091709A57800000090261A187000000092955A2040000000
     

    Seize-Resistant Helical Threaded Inserts

    Image of Product. Pronged. Bottom orientation. Threaded Inserts. Seize-Resistant Helical Threaded Inserts, Pronged.

    Pronged

    Install and remove screws repeatedly without sticking or binding. These inserts have a dry-film lubricant on their surface for smooth installation. 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.
    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.
    Dry-Film-Lubricated 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
     
    Dry-Film-Lubricated 18-8 Stainless Steel
    M2.5 x 0.45 mm2.537 Ga.
    		0.104"DIN 8140, SAE MA3280-101, MIL-I-8846191000A0160000091709A67800000091709A57800000090261A187000000092955A2040000000
    M2.5 x 0.45 mm537 Ga.
    		0.104"DIN 8140, SAE MA3280-201, MIL-I-8846191000A019000091709A6780000091709A5780000090261A18700000092955A204000000
     

    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
    M2.5
    		Helical Inserts, Screw-Locking Helical Inserts91049A362000000091049A503000000
     

    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
    2-56, 3-48, M2, M2.5StraightHelical Inserts, Screw-Locking Helical Inserts1231N1100000
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