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    35 Products
    About Threaded Inserts
    industrial info icon

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

    Key-Locking Threaded Inserts for Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Key-Locking Threaded Inserts for Soft Metal.
    Add strong threads in soft metal, such as aluminum. The keys on these inserts drive into holes to hold more securely than thread-locking or helical inserts. They prevent slipping and rotating, so they’re stable enough for use in vehicle or aerospace parts that experience heavy vibration. These inserts are comparable to Keensert inserts.
    To install, drill and tap a hole in your material. Then, thread the insert onto the installation tool and screw it into the hole. Place the tool over the keys and hit it with a hammer to drive them in.
    Standard Wall—Stronger than thin-wall inserts, these are your go-to choice for threading most holes.
    Black Phosphate-Coated Steel—These inserts resist occasional moisture.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Installation
    Tools
    Inserts with
    Installation Tools
    Each
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    1-9
    10-Up
    Each
    No. of Inserts
    Included
    Each
    Standard Wall
     
    Black Phosphate-Coated Steel
    3/4"-10
    1 1/8"-12
    1.125"1 1/16"
    1.063"40000000000000000000000000000000000003000000000000000
    3/4"-16
    1 1/8"-12
    1.125"1 1/16"
    1.063"4000000000000000000000000000000000300000000000000
    1 1/8"-12
    1 1/2"-12
    1.438"1 7/16"
    1.438"40000000000000000000000000000000000———0
     
    18-8 Stainless Steel
    3/4"-10
    1 1/8"-12
    1.125"1 1/16"
    1.063"40000000000000000000000000000000003000000000000000
    3/4"-16
    1 1/8"-12
    1.125"1 1/16"
    1.063"40000000000000000000000000000000003000000000000000
     

    Key-Locking Threaded Insert Assortments with Installation Tools

    Image of Product. Front orientation. Threaded Inserts. Key-Locking Threaded Insert Assortments with Installation Tools.
    What you need to add or repair a range of thread sizes in soft metal, such as aluminum. These assortments include multiple key-locking inserts of each size and an installation tool. They're comparable to Keensert inserts.
    Standard Wall—Stronger than thin-wall inserts, these are your go-to choice for threading most holes.
    Black Phosphate-Coated Steel—These inserts resist occasional moisture.
    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
    For Tap Thread Size
    Drill Bit Size
    For Max. Hole Dia.
    Each
    Standard Wall
     
    Black Phosphate-Coated Steel
    771"-12 Thread × 1 3/8" Installed Lg. (2 Each)
    1/2"-20 Thread × 5/8" Installed Lg. (6 Each)
    1/4"-28 Thread × 3/8" Installed Lg. (20 Each)
    3/4"-16 Thread × 1 1/8" Installed Lg. (3 Each)
    3/8"-24 Thread × 1/2" Installed Lg. (10 Each)
    5/16"-24 Thread × 0.438" Installed Lg. (15 Each)
    5/8"-18 Thread × 7/8" Installed Lg. (3 Each)
    7/16"-20 Thread × 5/8" Installed Lg. (10 Each)
    7/8"-14 Thread × 1 1/4" Installed Lg. (3 Each)
    9/16"-18 Thread × 0.813" Installed Lg. (5 Each)
    Installation Tool
    Fine
    7/16"-14
    1/2"-13
    9/16"-12
    5/8"-11
    3/4"-16
    7/8"-14
    1 1/8"-12
    1 1/4"-12
    1 3/8"-12
    29/64"
    33/64"
    37/64"
    45/64"
    53/64"
    1 1/16"
    1 3/16"
    1 5/16"
    X
    0.397"
    0.453"
    0.516"
    0.578"
    0.703"
    0.828"
    1.063"
    1.186"
    1.313"
    0000000000000000
    771"-8 Thread × 1 3/8" Installed Lg. (2 Each)
    1/2"-13 Thread × 5/8" Installed Lg. (6 Each)
    1/4"-20 Thread × 3/8" Installed Lg. (20 Each)
    3/4"-10 Thread × 1 1/8" Installed Lg. (3 Each)
    3/8"-16 Thread × 1/2" Installed Lg. (10 Each)
    5/16"-18 Thread × 0.438" Installed Lg. (15 Each)
    5/8"-11 Thread × 7/8" Installed Lg. (3 Each)
    7/16"-14 Thread × 5/8" Installed Lg. (10 Each)
    7/8"-9 Thread × 1 1/4" Installed Lg. (3 Each)
    9/16"-12 Thread × 0.813" Installed Lg. (5 Each)
    Installation Tool
    Coarse
    7/16"-14
    1/2"-13
    9/16"-12
    5/8"-11
    3/4"-16
    7/8"-14
    1 1/8"-12
    1 1/4"-12
    1 3/8"-12
    29/64"
    33/64"
    37/64"
    45/64"
    53/64"
    1 1/16"
    1 3/16"
    1 5/16"
    X
    0.397"
    0.453"
    0.516"
    0.578"
    0.703"
    0.828"
    1.063"
    1.186"
    1.313"
    000000000000000
     
    18-8 Stainless Steel
    771"-12 Thread × 1 3/8" Installed Lg. (2 Each)
    1/2"-20 Thread × 5/8" Installed Lg. (6 Each)
    1/4"-28 Thread × 3/8" Installed Lg. (20 Each)
    3/4"-16 Thread × 1 1/8" Installed Lg. (3 Each)
    3/8"-24 Thread × 1/2" Installed Lg. (10 Each)
    5/16"-24 Thread × 0.438" Installed Lg. (15 Each)
    5/8"-18 Thread × 7/8" Installed Lg. (3 Each)
    7/16"-20 Thread × 5/8" Installed Lg. (10 Each)
    7/8"-14 Thread × 1 1/4" Installed Lg. (3 Each)
    9/16"-18 Thread × 0.813" Installed Lg. (5 Each)
    Installation Tool
    Fine
    7/16"-14
    1/2"-13
    9/16"-12
    5/8"-11
    3/4"-16
    7/8"-14
    1 1/8"-12
    1 1/4"-12
    1 3/8"-12
    29/64"
    33/64"
    37/64"
    45/64"
    53/64"
    1 1/16"
    1 3/16"
    1 5/16"
    X
    0.397"
    0.453"
    0.516"
    0.578"
    0.703"
    0.828"
    1.063"
    1.186"
    1.313"
    000000000000000
    771"-8 Thread × 1 3/8" Installed Lg. (2 Each)
    1/2"-13 Thread × 5/8" Installed Lg. (6 Each)
    1/4"-20 Thread × 3/8" Installed Lg. (20 Each)
    3/4"-10 Thread × 1 1/8" Installed Lg. (3 Each)
    3/8"-16 Thread × 1/2" Installed Lg. (10 Each)
    5/16"-18 Thread × 0.438" Installed Lg. (15 Each)
    5/8"-11 Thread × 7/8" Installed Lg. (3 Each)
    7/16"-14 Thread × 5/8" Installed Lg. (10 Each)
    7/8"-9 Thread × 1 1/4" Installed Lg. (3 Each)
    9/16"-12 Thread × 0.813" Installed Lg. (5 Each)
    Installation Tool
    Coarse
    7/16"-14
    1/2"-13
    9/16"-12
    5/8"-11
    3/4"-16
    7/8"-14
    1 1/8"-12
    1 1/4"-12
    1 3/8"-12
    29/64"
    33/64"
    37/64"
    45/64"
    53/64"
    1 1/16"
    1 3/16"
    1 5/16"
    X
    0.397"
    0.453"
    0.516"
    0.578"
    0.703"
    0.828"
    1.063"
    1.186"
    1.313"
    000000000000000
     

    Mil.-Spec. Key-Locking Threaded Inserts For Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Mil.-Spec. Key-Locking Threaded Inserts For Soft Metal.
    These inserts are manufactured and tested to meet or compare to strict standards adopted by the U.S. military. The keys drive into aluminum and other soft metal for a secure hold that won't slip or rotate, even in vibrating vehicle or aerospace parts. These inserts are comparable to Keensert inserts.
    To install, drill and tap a hole in your material. Then, thread the insert onto the installation tool and screw it into the hole. Place the tool over the keys and hit it with a hammer to drive them in.
    Standard Wall—Stronger than thin-wall inserts, these are your go-to choice for threading most holes.
    High-Strength Cadmium-Plated Alloy Steel—These inserts have the strength to stand up to high-pressure applications and a plating that helps screws thread in smoothly.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Installation
    Tools
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    Specs. Met
    Each
    Each
    Standard Wall
     
    High-Strength Cadmium-Plated Alloy Steel
    3/4"-10
    1 1/8"-12
    1.125"1 1/16"
    1.062"4MS51831A1090000000000000000000000000000000
    3/4"-16
    1 1/8"-12
    1.125"1 1/16"
    1.062"4MS51831A20900000000000000———0
     
    18-8 Stainless Steel
    3/4"-10
    1 1/8"-12
    1.125"1 1/16"
    1.067"4MS51831-10900000000000000000000000000000
    3/4"-16
    1 1/8"-12
    1.125"1 1/16"
    1.067"4MS51831-20900000000000000———0
     

    Key-Locking Threaded Insert Drivers

    Image of Product. Front orientation. Threaded Insert Installation Tools. Key-Locking Threaded Insert Drivers.
    Place the tip of these tools into a key-locking insert after you've threaded it into a hole with your fingers. Then, strike these tools with a hammer to drive the keys into the material and secure the insert. They’re compatible with Keensert inserts.
    Choose the tool that matches your insert’s thread size and tap thread size.
    For Thread Size
    For Tap Thread
    Size
    Handle
    Style
    Each
    Standard (UN) Thread
     
    For Thick-Wall Inserts
    3/4"-10, 3/4"-161 1/8"-12
    Straight000000000000000
    1 1/8"-7, 1 1/8"-121 1/2"-12
    Straight000000000000000
     

    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
    7/8"-9, 7/8"-14, 1"-8, 1"-12, 1"-14, 1 1/8"-7, 1 1/8"-12, 1 1/4"-7, 1 1/4"-12, 1 3/8"-6, 1 3/8"-12, 1 1/2"-6, 1 1/2"-12, M20, M22, M24, M26, M27, M30, M33, M36, M39
    000000000000000
     
    Narrow Profile
    1 1/8"-7, 1 1/8"-12, 1 1/4"-7, 1 1/4"-8, 1 1/4"-12, 1 3/8"-6, 1 3/8"-12, 1 1/2"-6, 1 1/2"-8, 1 1/2"-12, M27, M30, M36, M39
    Heli-Coil000000000000000
     

    Key-Locking Threaded Inserts with Installation Tools

    Image of Product. Front orientation. Threaded Inserts. Key-Locking Threaded Inserts with Installation Tools.
    Paired with the right tool for installation, these inserts create strong threads in soft metal, such as aluminum. They have keys that drive into material to prevent inserts from slipping and rotating in the hole.
    Standard Wall—Stronger than thin-wall inserts, these are your go-to choice for threading most holes.
    Black Phosphate-Coated Steel—These inserts resist occasional moisture.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    No. of Inserts
    Included
    Each
    Standard Wall
     
    Black Phosphate-Coated Steel
    3/4"-10
    1 1/8"-12
    1.125"1 1/16"
    1.063"43000000000000000
    3/4"-16
    1 1/8"-12
    1.125"1 1/16"
    1.063"4300000000000000
     
    18-8 Stainless Steel
    3/4"-10
    1 1/8"-12
    1.125"1 1/16"
    1.063"43000000000000000
    3/4"-16
    1 1/8"-12
    1.125"1 1/16"
    1.063"43000000000000000
     

    Screw-Locking Seize-Resistant Key-Locking Threaded Inserts for Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Screw-Locking Seize-Resistant Key-Locking Threaded Inserts for Soft Metal.
    Create the tightest hold in aluminum and other soft metal without screws sticking. The lubricant on these inserts eases installation, and the irregularly shaped threads won’t let screws back out from vibration. Inserts have keys that drive into material to prevent them from slipping or rotating in the hole.
    To install, drill and tap a hole in your material. Then, thread the insert onto the installation tool and screw it into the hole. Place the tool over the keys and hit it with a hammer to drive them in.
    Standard Wall—Stronger than thin-wall inserts, these are your go-to choice for threading most holes.
    Dry-Film-Lubricated Cadmium-Plated Steel—The plating creates a barrier against rust.
    Dry-Film-Lubricated 18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Installation
    Tools
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    Specs. Met
    Each
    Each
    Standard Wall
     
    Dry-Film-Lubricated Cadmium-Plated Steel
    3/4"-10
    1 1/8"-12
    1.250"1 1/16"
    1.063"4MS51831A109L0000000000000000000000000000000
     
    Dry-Film-Lubricated 18-8 Stainless Steel
    3/4"-10
    1 1/8"-12
    1.250"1 1/16"
    1.063"4MS51831-109L00000000000000000000000000000
     

    Key-Locking Threaded Insert Installation Tools

    Image of Product. Front orientation. Threaded Insert Installation Tools. Key-Locking Threaded Insert Installation Tools, Style A.
    Image of Product. Front orientation. Threaded Insert Installation Tools. Key-Locking Threaded Insert Installation Tools, Style D.

    Style A

    Style D

    Thread inserts and drive down their keys with a single tool. These tools are compatible with Keensert inserts.
    Threaded Insert Installation Tools
    Image of Product. Front orientation. Threaded Insert Installation Tools. Key-Locking Threaded Insert Installation Tools, Style A.

    Style A

    For Thread Size
    For Tap Thread
    Size
    Style
    Features
    Each
    For Thick-Wall Inserts
    3/4"-10, 3/4"-161 1/8"-12
    ASlotted End0000000000000
    1 1/8"-7, 1 1/8"-121 1/2"-12
    ASlotted End000000000000
     
    Threaded Insert Installation Tools with Spring
    Image of Product. Front orientation. Threaded Insert Installation Tools. Key-Locking Threaded Insert Installation Tools, Style D.

    Style D

    The tradespersons’ choice for installing Mil. Spec. inserts. A spring holds the sleeve under tension, so wobbles and jostles don’t interfere with a clean, professional install.
    For Thread Size
    For Tap Thread
    Size
    Style
    Features
    Each
    For Thick-Wall Inserts
    3/4"-10, 3/4"-161 1/8"-12
    DSleeve, Slotted End0000000000000000
     

    Finish-Your-Own Key-Locking Threaded Inserts for Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Finish-Your-Own Key-Locking Threaded Inserts for Soft Metal.
    Image of Specification. Side1 orientation. Contains Annotated. Threaded Inserts. Finish-Your-Own Key-Locking Threaded Inserts for Soft Metal.
    Tap the thread size you need into the solid body of these inserts. They’re a great choice when you need a custom combination of internal thread size and external diameter. Use them to repair or add new threads in soft metal, such as aluminum. They can also plug threaded holes without the hassle of welding. Keys on the inserts drive into material to prevent slipping and rotating in the hole.
    To install, drill and tap a hole in your material. Then, thread the insert onto the installation tool and screw it into the hole. Place the tool over the keys and hit it with a hammer to drive them in.
    Black Phosphate-Coated Steel—These inserts resist occasional moisture.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Installation
    Tools
    For Tap Thread
    Size
    Installed
    Lg.
    Max. Tapping
    Dia.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    Each
    Each
    Standard Profile
     
    Black Phosphate-Coated Steel
    1 1/8"-12
    1.125"3/4"1 1/16"
    1.063"40000000000000000000000000000000
     
    18-8 Stainless Steel
    1 1/8"-12
    1.125"3/4"1 1/16"
    1.063"4000000000000000000000000000000
     

    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
    Inserts with
    Installation Tools
    Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    No. of Inserts
    Included
    Each
    Pronged
     
    18-8 Stainless Steel
    1 1/8"-12
    1.125"1 5/32"
    1.156"MS12466610000000000000000000000000000000000000000000000———0
    1 1/8"-12
    1.688"1 5/32"
    1.156"MS1247061000000000000000000000000000000000000000000050000000000000000
     
    Extraction Tools

    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.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Inserts
    Included
    Includes
    Each
    Pronged
     
    18-8 Stainless Steel
    1 1/8"-12
    1.688"1 5/32"
    1.156"5Drill Bit
    Installation Tool
    Through-Hole Tap
    0000000000000000
     

    Key-Locking Threaded Insert Blank Drivers

    Image of Product. Front orientation. Threaded Insert Installation Tools. Key-Locking Threaded Insert Blank Drivers.
    Hand thread an insert blank into a tapped hole before placing the tip of these tools on the insert. Strike the tool with a hammer to drive the keys into your material.
    For Tap Thread
    Size
    Handle
    Style
    Each
    Standard (UN) Thread
    1 1/8"-12
    Straight0000000000000000
     

    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. 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.

    T-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
    1 1/8"-12
    Heli-CoilT-HandleThreadedHelical Inserts, Screw-Locking Helical Inserts0000000000000000
     
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