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    24 Products

    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
    Inserts with
    Installation Tools
    Thread
    Size
    Installed
    Lg.
    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
    5/8"-11
    		0.625"21/32"
    		0.656"MS122087591732A3940000091709A11200000091709A473000000090261A172000000698356A1480000000
    5/8"-11
    		0.938"21/32"
    		0.656"MS122127191732A218000091709A1120000091709A47300000090261A17200000691732A018000000
    5/8"-11
    		1.250"21/32"
    		0.656"MS122167191732A395000091709A1120000091709A47300000090261A17200000698356A149000000
    5/8"-11
    		1.562"21/32"
    		0.656"MS122207591732A227000091709A1120000091709A47300000090261A17200000————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
    		90254A330000000
     

    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
    		—90254A113000000
     
    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-Coil90254A33000000
     

    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
    541/2"-13 Thread × 3/4" Installed Lg. (6 Each)
    1/4"-20 Thread × 3/8" Installed Lg. (12 Each)
    3/8"-16 Thread × 0.562" Installed Lg. (12 Each)
    5/16"-18 Thread × 0.469" Installed Lg. (12 Each)
    5/8"-11 Thread × 15/16" Installed Lg. (6 Each)
    7/16"-14 Thread × 0.656" Installed Lg. (6 Each)
    Drill Bits
    Installation Tools
    Through-Hole Taps    		Coarse
    		17/64"
    21/64"
    25/64"
    29/64"
    17/32"
    21/32"
    		0.266"
    0.328"
    0.391"
    0.453"
    0.531"
    0.656"    		90285A1210000000
     

    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
    5/8"-11
    		2"4 1/4"UNC
    		421/32"
    		0.6563"Square91709A11200000091709A4730000000
     

    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.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Inserts
    Included
    Includes
    Each
    Pronged
     
    18-8 Stainless Steel
    5/8"-11
    		0.625"21/32"
    		0.656"6Drill Bit
    Installation Tool
    Through-Hole Tap    		98356A1480000000
    5/8"-11
    		0.938"21/32"
    		0.656"6Drill Bit
    Installation Tool
    Through-Hole Tap    		91732A018000000
    5/8"-11
    		1.250"21/32"
    		0.656"6Drill Bit
    Installation Tool
    Through-Hole Tap    		98356A149000000
     

    Helical Threaded Insert Installation Tools

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

    No Handle

    T-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
    Handle
    Style
    Shank
    Type
    For Use With
    Each
    Standard (UN) Thread
    5/8"-11
    		—SquareHelical Inserts, Screw-Locking Helical Inserts93060A021000000
    5/8"-11
    		T-Handle—Helical Inserts, Screw-Locking Helical Inserts90261A17200000
     

    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
    Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Pronged
     
    18-8 Stainless Steel
    5/8"-11
    		0.625"21/32"
    		0.656"MS21209C1010, NASM21209190296A1510000091709A11200000091709A473000000090261A172000000
    5/8"-11
    		0.938"21/32"
    		0.656"MS21209C1015, NASM21209190296A152000091709A1120000091709A47300000090261A17200000
    5/8"-11
    		1.250"21/32"
    		0.656"MS21209C1020, NASM21209190296A153000091709A1120000091709A47300000090261A17200000
     

    Left-Hand-Thread Helical Threaded Inserts

    Image of Product. Bottom orientation. Threaded Inserts. Left-Hand-Thread Helical Threaded Inserts.
    Fix threads in parts that rotate counterclockwise. Pair these inserts with left-hand-thread screws and turn them to the left to tighten. 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
    Installation
    Tools
    Inserts with
    Installation Tools
    Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    No. of Inserts
    Included
    Each
    Pronged
     
    18-8 Stainless Steel
    5/8"-11
    		0.938"21/32"
    		0.656"192090A1510000092090A35100000092450A185000000292090A6550000000
     
    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
    		90254A330000000
     

    Left-Hand Thread Helical Threaded Inserts with Installation Tools

    Image of Product. Front orientation. Threaded Inserts. Left-Hand Thread Helical Threaded Inserts with Installation Tools.
    Save time when repairing threads in parts that rotate counterclockwise—these inserts come with installation tools. Pair them with left-hand-thread screws, and turn them the left to tighten. 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.
    Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Inserts
    Included
    Includes
    Each
    Pronged
     
    18-8 Stainless Steel
    5/8"-11
    		0.938"21/32"
    		0.656"2Installation Tool
    Through-Hole Tap    		92090A6550000000
     

    Go/No-Go Helical Insert Threaded Plug Gauges with Handle

    Image of Product. Front orientation. Plug Gauges. Go/No-Go Helical Insert Threaded Plug Gauges with Handle.
    Check that holes tapped for helical threads are within tolerance. You’ll sometimes hear these threads referred to as Screw Thread Insert (STI) threads. To speed up tests, these gauges have a go gauge on one end and a no-go gauge on the other. The double-ended taperlock handle makes them quick to thread and unthread. It also lets you swap in new plug gauges (not included) in place of worn ones.
    The go gauge checks the minimum internal thread size, and the no-go gauge checks the maximum. A part is within tolerance if it’s easy to thread the go gauge but difficult to thread the no-go gauge more than two turns.
    Plug Gauges with Accuracy Certificate Traceable to NIST—Gauges with an accuracy certificate traceable to NIST include verification from the manufacturer that their thread sizes are within tolerance. The certificate is also known as a certificate of compliance or a short-form certification.
    Plug Gauges with Calibration Certificate Traceable to NIST—Gauges with a calibration certificate traceable to NIST were calibrated in a lab. The certificate, sometimes called a test report or long-form certificate, details the tested measurements.
    Plug Gauges with Accuracy
    Certificate Traceable to NIST
    Plug Gauges with Calibration
    Certificate Traceable to NIST
    Thread
    Size
    Thread
    Type
    Pitch Dia.
    Tolerance
    Hardness
    Material
    Features
    For Thread Fit
    Each
    Each
    Class X Gauge
    5/8"-11
    		UNC
    		-0.0003" to 0.0003"Rockwell C70Chrome-Plated Tool SteelDouble-Ended Taperlock HandleUnified Standard Class 2B
    		7941N2600000007941N440000000
     

    Left-Hand Thread Helical Insert Taps

    Image of Product. Front orientation. Taps. Left-Hand Thread Helical Insert Taps.
    Size holes for installing helical inserts that anchor left-hand bolts and rods. Helical inserts reinforce the connection between holes and fasteners that secure counter-clockwise rotating parts. Left-hand threads keep components such as flywheels and propellers from loosening and spinning off.
    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.
    Drill Bit
    Plug Chamfer
    For Insert
    Size
    Thread
    Lg.
    Overall
    Lg.
    For Insert
    Thread Type
    No. of
    Flutes
    Size
    Decimal Size
    Equiv.
    Shank
    Type
    Each
    High-Speed Steel
     
    Uncoated
    5/8"-11
    		1 13/16"4 1/4"UNC
    		421/32"
    		0.6563"Square92090A351000000
     

    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.
    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.

    T-Handle

    Prong Slot 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.
    For Thread
    Size
    Handle
    Style
    Helical Insert
    Tool Drive Type
    For Use With
    Each
    Standard (UN) Thread
    5/8"-11
    		T-HandleProng SlotHelical Inserts, Screw-Locking Helical Inserts1338N370000000
     

    Helical Threaded Insert Installation and Prong Break-Off Tools

    Image of Product. Front orientation. Threaded Insert Installation Tools. Helical Threaded Insert Installation and Prong Break-Off Tools, T-Handle.

    T-Handle

    Install helical inserts and break off prongs with one tool and a hammer strike. These tools have a slot that grips your insert’s prong for turning both left- and right-hand threads. Slide an insert onto these tools and drive them a quarter-turn to half-turn below the material’s surface. Then, strike the end of the tool with a hammer to break off the prong. These tools work with pronged helical inserts.
    For Thread Size
    For Pipe
    Size
    Handle
    Style
    Each
    5/8"-11, 5/8"-18, M16 × 1.5 mm, M16 × 2 mm3/8 NPTT-Handle92450A185000000
     
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