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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.
    Extra-Thick Wall—Stronger than standard- and thin-wall inserts, use them to reduce the size of tapped holes or replace threads that have been drilled out.
    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
    1"-8
    1 3/8"-12
    1.375"1 5/16"
    1.313"490245A04200000000000092100A744000000290245A0220000000
    1"-12
    1 3/8"-12
    1.375"1 5/16"
    1.313"490245A082000000000092100A74400000290245A06200000
    1"-14
    1 3/8"-12
    1.375"1 5/16"
    1.313"490245A085000000000092100A74400000290245A07000000
     
    18-8 Stainless Steel
    1"-8
    1 3/8"-12
    1.375"1 5/16"
    1.313"491731A083000000000092100A74400000291731A044000000
    1"-12
    1 3/8"-12
    1.375"1 5/16"
    1.313"491731A088000000000092100A74400000———0
     
    Extra-Thick Wall
     
    Black Phosphate-Coated Steel
    7/8"-9
    1 3/8"-12
    1.250"1 5/16"
    1.313"493302A630000000000093302A73000000———0
     
    18-8 Stainless Steel
    7/8"-9
    1 3/8"-12
    1.250"1 5/16"
    1.313"493340A83300000000000093302A73000000———0
     

    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"
    90284A2150000000
    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"
    90284A211000000
     
    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"
    90284A415000000
    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"
    90284A411000000
     

    Thread-Locking Threaded Inserts

    Image of Product. Bottom orientation. Threaded Inserts. Thread-Locking Threaded Inserts.
    With Loctite® adhesive already on the threads, these inserts won’t back out or vibrate loose. The adhesive reaches full strength after 72 hours. Unlike helical inserts, you can install them with a standard drill and tap. However, thread-locking inserts are difficult to remove and reuse.
    After drilling and tapping your hole, install inserts with a wrench or an installation bit. To use a wrench, thread an insert and two hex nuts onto a bolt. Then, grip and turn the top nut to drive into the hole. For slotted inserts, you can drive with a slotted screwdriver instead.
    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.
    Inserts
    Installation
    Tools
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Drive
    Style
    Pkg.
    Qty.
    Pkg.
    Each
    Standard Wall
     
    Black Phosphate-Coated Steel
    1"-8
    1 3/8"-12
    1.250"1 9/32"
    1.281"Slotted
    190248A05400000094110A240000000
    1"-14
    1 3/8"-12
    1.250"1 9/32"
    1.281"Slotted
    190248A0890000094110A24000000
     

    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.
    Extra-Thick Wall—Stronger than standard- and thin-wall inserts, use them to reduce the size of tapped holes or replace threads that have been drilled out.
    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
    1"-8
    1 3/8"-12
    1.375"1 5/16"
    1.312"4MS51831A11195101A13900000093904A7530000000
     
    18-8 Stainless Steel
    1"-8
    1 3/8"-12
    1.375"1 5/16"
    1.317"4MS51831-11193904A2520000093904A753000000
    1"-12
    1 3/8"-12
    1.375"1 5/16"
    1.317"4MS51831-21193904A2540000093904A753000000
     
    Extra-Thick Wall
     
    18-8 Stainless Steel
    7/8"-9
    1 3/8"-12
    1.250"1 5/16"
    1.317"4MS51832-11093904A2480000093904A77500000
     

    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
    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, M27, M30, M33, M36, M39
    90254A114000000
     
    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-Coil90254A360000000
     

    Thread-Locking Threaded Insert Assortments

    Image of Product. Front orientation. Threaded Inserts. Thread-Locking Threaded Insert Assortments.
    These assortments include various sizes of thread-locking inserts, which won’t back out or loosen from vibration. Also known as E-Z Lok, they come with Loctite® adhesive already applied, and the adhesive reaches full strength after 72 hours. After drilling and tapping your hole, install inserts with a wrench or use an installation bit (not included). To use a wrench, thread an insert and two hex nuts onto a bolt. Then, grip and turn the top nut to drive into 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.
    No. of Inserts
    Included
    Includes
    Thread
    Spacing
    For Tap Thread
    Size
    Drill Bit
    Size
    For Maximum
    Hole Diameter
    Drive
    Style
    Each
    Standard Wall
     
    Black Phosphate-Coated Steel
    221"-14 Thread × 1 1/4" Installed Lg. (2 Each)
    1/2"-20 Thread × 0.656" Installed Lg. (6 Each)
    3/4"-16 Thread × 0.781" Installed Lg. (7 Each)
    5/8"-18 Thread × 0.688" Installed Lg. (7 Each)
    Fine
    3/4"-10
    7/8"-9
    1"-8
    1 3/8"-12
    21/32"
    49/64"
    7/8"
    1 9/32"
    21/32"
    49/64"
    7/8"
    1 9/32"
    Slotted
    90248A115000000
    221"-8 Thread × 1 1/4" Installed Lg. (2 Each)
    1/2"-13 Thread × 0.656" Installed Lg. (6 Each)
    3/4"-10 Thread × 0.781" Installed Lg. (7 Each)
    5/8"-11 Thread × 0.688" Installed Lg. (7 Each)
    Coarse
    3/4"-10
    7/8"-9
    1"-8
    1 3/8"-12
    21/32"
    49/64"
    7/8"
    1 9/32"
    21/32"
    49/64"
    7/8"
    1 9/32"
    Slotted
    90248A11100000
     

    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
    1"-8, 1"-12, 1"-141 3/8"-12
    Straight92100A744000000
     
    For Extra-Thick-Wall Inserts
    7/8"-9, 7/8"-141 3/8"-12
    Straight93302A73000000
     

    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
    1"-8
    1 3/8"-12
    1.375"1 5/16"
    1.313"4290245A0220000000
    1"-12
    1 3/8"-12
    1.375"1 5/16"
    1.313"4290245A06200000
    1"-14
    1 3/8"-12
    1.375"1 5/16"
    1.313"4290245A07000000
     
    18-8 Stainless Steel
    1"-8
    1 3/8"-12
    1.375"1 5/16"
    1.313"4291731A044000000
     

    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
    1"-8, 1"-12, 1"-141 3/8"-12
    ASlotted End6721N44000000
     
    For Extra-Thick-Wall Inserts
    7/8"-9, 7/8"-141 3/8"-12
    ASlotted End6721N6300000
     
    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
    1"-8, 1"-121 3/8"-12
    DSleeve, Slotted End93904A7530000000
     
    For Extra-Thick-Wall Inserts
    7/8"-9
    1 3/8"-12
    DSleeve, Slotted End93904A77500000
     

    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 18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    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 18-8 Stainless Steel
    1"-8
    1 3/8"-12
    1.500"1 5/16"
    1.313"4MS51831-111L97255A15300000093904A7530000000
     

    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.
    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 3/8"-12
    1.375"1"1 5/16"
    1.313"493774A23000000093741A2300000000
     

    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 3/8"-12
    Straight93741A2300000000
     
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