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    10 Products
    About Threaded Inserts
    industrial info icon

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

    Performance

    Certification

    Sold As

    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
    Prong
    Break-Off Tools
    Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Each
    Pronged
     
    18-8 Stainless Steel
    3-48
    		0.099"7/64"
    		0.109"MS1221151091732A2050000091709A09900000091709A40400000090261A150000000092955A1010000000
    3-48
    		0.148"7/64"
    		0.109"MS1221551091732A207000091709A0990000091709A4040000090261A15000000092955A101000000
     
    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
    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
     

    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
    2881-64 Thread × 0.11" Installed Lg. (24 Inserts and 24 Screw-Locking Inserts)
    2-56 Thread × 0.129" Installed Lg. (24 Inserts and 24 Screw-Locking Inserts)
    3-48 Thread × 0.148" Installed Lg. (24 Inserts and 24 Screw-Locking Inserts)
    4-40 Thread × 0.168" Installed Lg. (24 Inserts and 24 Screw-Locking Inserts)
    6-32 Thread × 0.207" Installed Lg. (24 Inserts and 24 Screw-Locking Inserts)
    8-32 Thread × 0.246" Installed Lg. (24 Inserts and 24 Screw-Locking Inserts)
    Drill Bits
    Installation Tools
    Through-Hole Taps    		Coarse
    		5/64"
    3/32"
    36 Ga.
    31 Ga.
    26 Ga.
    17 Ga.
    		0.078"
    0.094"
    0.107"
    0.120"
    0.147"
    0.173"    		90285A1340000000
     

    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
    Prong
    Break-Off Tools
    Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Each
    Pronged
     
    18-8 Stainless Steel
    3-48
    		0.099"7/64"
    		0.109"MS21209C0310, NASM21209590296A1840000091709A09900000091709A40400000090261A150000000092955A1010000000
    3-48
    		0.148"7/64"
    		0.109"MS21209C0315, NASM212091090296A098000091709A0990000091709A4040000090261A15000000092955A101000000
     
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