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    18 Products

    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
    Inserts with
    Installation Tools
    Thread Size
    Installed
    Lg., mm
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    No. of Inserts
    Included
    Each
    Pronged
     
    18-8 Stainless Steel
    M16 x 1.5 mm2421/32"
    		0.656"SAE MA3279-1676000000000000000000000000000000000000000000000000000000000000000————0
    M16 x 2 mm1616.5 mm
    		16.5 mmDIN 8140, SAE MA3279-1181000000000000000000000000000000000000000000000000000000000————0
    M16 x 2 mm2416.5 mm
    		16.5 mmDIN 8140, SAE MA3279-168100000000000000000000000000000000000000000000000000000000060000000000000000
    M16 x 2 mm3216.5 mm
    		16.5 mmDIN 8140, SAE MA3279-2181000000000000000000000000000000000000000000000000000000000————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 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
     

    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
    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
    		—000000000000000
     
    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
    M16
    		2"4 1/4"Metric
    		421/32"
    		0.6563"Square00000000000000000000000000000000
    M16
    		2"4 1/4"Metric
    		416.5 mm
    		0.6496"Square00000000000000000000000000000
     

    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, T-Handle.

    T-Handle

    Image of Specification. Prong Slot Drive. Front orientation. ZoomedIn view. Prong Slot Drive Helical Insert Tool. Easy-Start Helical Threaded Insert Installation Tools, Threaded Insert Installation Tools with Depth Stop.
    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.

    Prong Slot Drive

    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.
    Prong Slot Drive Helical Insert Tool—Install both left- and right-hand threaded inserts with any thread pitch. However, these tools don't align the threads like threaded-drive tools, so installation may be more difficult.
    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
    M16 × 1.5 mm—T-HandleProng SlotHelical Inserts, Screw-Locking Helical Inserts0000000000000000
    M16 × 2 mm—T-HandleProng SlotHelical Inserts, Screw-Locking Helical Inserts0000000000000
    M16 × 2 mmHeli-CoilT-HandleThreadedHelical Inserts, Screw-Locking Helical Inserts000000000000000
     

    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.
    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
    M16 x 2 mm2421/32"
    		0.656"6Drill Bit
    Installation Tool
    Through-Hole Tap    		0000000000000000
     

    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
    Thread
    Size
    Installed
    Lg., mm
    Drill Bit
    Size, mm
    For Max.
    Hole Dia., mm
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Pronged
     
    18-8 Stainless Steel
    M16 x 2 mm1616.5
    		16.5DIN 8140, SAE MA3329-118100000000000000000000000000000000000000000000000000000000000000
    M16 x 2 mm2416.5
    		16.5DIN 8140, SAE MA3329-1681000000000000000000000000000000000000000000000000000000000
     

    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
    M16 × 1.5 mmSquareHelical Inserts, Screw-Locking Helical Inserts000000000000000
    M16 × 2 mmSquareHelical Inserts, Screw-Locking Helical Inserts00000000000000
     
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