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    81 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.

    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.
    Nickel—More resistant to acids and salt water than stainless steel inserts.
    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
     
    Nickel
    2-56
    		0.129"41 Ga.
    		0.096"1000000000000000000000000000000000000000000000000000000000000000000000000000
    6-32
    		0.138"25 Ga.
    		0.150"10000000000000000000000000000000000000000000000000000000000000000000000
    10-24
    		0.190"5 Ga.
    		0.206"10000000000000000000000000000000000000000000000000000000000000000000000
    10-24
    		0.380"5 Ga.
    		0.206"10000000000000000000000000000000000000000000000000000000000000000000000
    10-32
    		0.285"13/64"
    		0.203"10000000000000000000000000000000000000000000000000000000000000000000000
    1/4"-20
    		0.250"H
    		0.266"10000000000000000000000000000000000000000000000000000000000000000000000
    1/4"-20
    		0.375"H
    		0.266"10000000000000000000000000000000000000000000000000000000000000000000000
    5/16"-18
    		0.312"Q
    		0.332"100000000000000000000000000000000000000000000000000000000000000000000000
    5/16"-18
    		0.469"Q
    		0.332"100000000000000000000000000000000000000000000000000000000000000000000000
    5/16"-18
    		0.625"Q
    		0.332"1000000000000000000000000000000000000000000000000000000000000000000000000
    3/8"-16
    		0.375"X
    		0.397"100000000000000000000000000000000000000000000000000000000000000000000000
    3/8"-16
    		0.562"X
    		0.397"100000000000000000000000000000000000000000000000000000000000000000000000
    3/8"-16
    		0.750"X
    		0.397"1000000000000000000000000000000000000000000000000000000000000000000000000
    M3 x 0.5 mm3 mm3.2 mm
    		3.2 mm100000000000000000000000000000000000000000000000000000000000000000000000
    M3 x 0.5 mm6 mm3.2 mm
    		3.2 mm100000000000000000000000000000000000000000000000000000000000000000000000
    M4 x 0.7 mm4 mm4.25 mm
    		4.25 mm100000000000000000000000000000000000000000000000000000000000000000000000
    M4 x 0.7 mm6 mm4.25 mm
    		4.25 mm100000000000000000000000000000000000000000000000000000000000000000000000
    M4 x 0.7 mm8 mm4.25 mm
    		4.25 mm100000000000000000000000000000000000000000000000000000000000000000000000
    M5 x 0.8 mm7.5 mm5.3 mm
    		5.3 mm10000000000000000000000000000000000000000000000000000000000000000000000
    M5 x 0.8 mm10 mm5.3 mm
    		5.3 mm10000000000000000000000000000000000000000000000000000000000000000000000
    M6 x 1 mm9 mm6.3 mm
    		6.3 mm10000000000000000000000000000000000000000000000000000000000000000000000
    M6 x 1 mm12 mm6.3 mm
    		6.3 mm10000000000000000000000000000000000000000000000000000000000000000000000
    M8 x 1.25 mm8 mm8.4 mm
    		8.4 mm1000000000000000000000000000000000000000000000000000000000000000000000000
    M8 x 1.25 mm12 mm8.4 mm
    		8.4 mm100000000000000000000000000000000000000000000000000000000000000000000000
    M8 x 1.25 mm16 mm8.4 mm
    		8.4 mm1000000000000000000000000000000000000000000000000000000000000000000000000
    M10 x 1.5 mm10 mm10.5 mm
    		10.5 mm1000000000000000000000000000000000000000000000000000000000000000000000000
    M10 x 1.5 mm15 mm10.5 mm
    		10.5 mm100000000000000000000000000000000000000000000000000000000000000000000000
     
    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
    2-56, 2-64, M2.2
    		000000000000000
    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
    		00000000000000
    10-24, 10-32, 12-24, 12-28, 1/4"-20, 1/4"-28, 1/4"-32, 1/4"-80, 5/16"-18, 5/16"-24, 5/16"-32, 3/8"-16, 3/8"-24, M5, M6, M7, M8, M10
    		00000000000000
     
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