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    16 Products
    About Threaded Inserts
    industrial info icon

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

    Helical Threaded Inserts

    Image of Product. Pronged. Bottom orientation. Threaded Inserts. Helical Threaded Inserts, Pronged.
    Image of Product. Prongless. Bottom orientation. Threaded Inserts. Helical Threaded Inserts, Prongless.

    Pronged

    Prongless

    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.
    Prongless—Without a prong to break off and retrieve, these inserts save time and avoid leftover debris in holes.
    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.
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Each
    Pronged
     
    18-8 Stainless Steel
    1-64
    		0.073"46 Ga.
    		0.081"1091732A0040000091709A09000000091709A68300000090261A131000000092955A2010000000
    1-64
    		0.110"46 Ga.
    		0.081"1091732A008000091709A0900000091709A6830000090261A13100000092955A201000000
    1-64
    		0.146"46 Ga.
    		0.081"1091732A011000091709A0900000091709A6830000090261A13100000092955A201000000
     
    Prongless
     
    18-8 Stainless Steel
    1-64
    		0.073"46 Ga.
    		0.081"591990A504000091709A0900000091709A6830000091049A101000000———0
    1-64
    		0.110"46 Ga.
    		0.081"591990A505000091709A0900000091709A6830000091049A101000000———0
    1-64
    		0.146"46 Ga.
    		0.081"591990A506000091709A0900000091709A6830000091049A101000000———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 Prongless Helical Inserts—Remove prongless inserts without damaging threads or the surface of your material. These tools also back out or adjust inserts that are installed too deep.
    For Thread
    Size
    Each
    For Pronged Helical Inserts
    1-64, 1-72, M2
    		90254A3700000000
     
    For Prongless Helical Inserts
    1-64
    		91049A377000000
     

    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.
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Each
    Pronged
     
    18-8 Stainless Steel
    1-64
    		0.073"46 Ga.
    		0.081"590296A0040000091709A09000000091709A68300000090261A131000000092955A2010000000
    1-64
    		0.110"46 Ga.
    		0.081"590296A008000091709A0900000091709A6830000090261A13100000092955A201000000
     

    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
     
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