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    106 Products
    About Threaded Inserts
    industrial info icon

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

    Mold-In Threaded Inserts for Plastic

    Image of Product. Bottom orientation. Threaded Inserts. Mold-In Threaded Inserts for Plastic.
    Mold the strongest metal threads into plastic parts. Designed for injection molding, these inserts become inseparable from your part. They form a stronger bond than heat-set and press-fit inserts and are better for frequent use than threads cut directly into material. Unlike heat-set inserts, they can be used in a wide variety of plastics, including thermoset plastics that can’t be reformed.
    To install, position these inserts in your mold cavity with a core pin (not included).
    Brass—Conductive and nonmagnetic, these inserts are useful for electrical applications. They resist moisture but aren't as strong as steel inserts.
    Lightweight Aluminum—At one-third the weight of steel or brass, use these inserts in robotics, aerospace parts, and other applications with strict weight limits. They also resist rust about as well as stainless steel but aren't as strong. Since inserts are lead-free, they can be safely recycled.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals. Since they’re lead-free, they can be safely recycled.
    Thread Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    For Core
    Pin Dia.
    Pkg.
    Qty.
    Pkg.
    Brass
    2-56
    0.156"30 Ga.
    0.133"0.072"257588N5900000
    4-40
    0.187"19 Ga.
    0.169"0.089"257588N6100000
    6-32
    0.250"8 Ga.
    0.200"0.110"257588N6200000
    8-32
    0.281"1 Ga.
    0.232"0.136"257588N6300000
    10-24
    0.312"H
    0.266"0.154"257588N6400000
    10-32
    0.312"H
    0.266"0.161"257588N6500000
    1/4"-20
    0.468"25/64"
    0.391"0.204"257588N6600000
    1/4"-28
    0.468"25/64"
    0.391"0.215"257588N670000
    5/16"-18
    0.562"33/64"
    0.516"0.261"107588N6800000
    3/8"-16
    0.687"14.5 mm
    0.578"0.318"57588N690000
    1/2"-13
    0.875"49/64"
    0.766"0.430"17588N710000
    M2 x 0.4 mm3.96 mm30 Ga.
    3.37 mm1.700 mm257588N7200000
    M3 x 0.5 mm4.75 mm19 Ga.
    4.29 mm2.500 mm257588N7300000
    M3.5 x 0.6 mm6.35 mm8 Ga.
    5.08 mm3.000 mm257588N7400000
    M4 x 0.7 mm7.14 mm1 Ga.
    5.89 mm3.400 mm257588N7500000
    M5 x 0.8 mm7.92 mmH
    6.75 mm4.300 mm257588N7600000
    M6 x 1 mm11.89 mm25/64"
    9.93 mm5.100 mm107588N770000
    M8 x 1.25 mm14.27 mm33/64"
    13.1 mm6.800 mm57588N780000
    M10 x 1.5 mm17.45 mm14.5 mm
    14.68 mm8.600 mm57588N790000
    M12 x 1.75 mm22.23 mm49/64"
    19.45 mm10.300 mm57588N810000
     
    Lightweight Aluminum
    4-40
    0.187"19 Ga.
    0.169"0.089"257588N120000
    6-32
    0.250"8 Ga.
    0.200"0.110"257588N130000
    8-32
    0.256"I
    0.272"0.136"257588N2300000
    10-24
    0.325"N
    0.309"0.148"257588N2400000
    1/4"-20
    0.394"23/64"
    0.367"0.200"107588N250000
    5/16"-18
    0.463"29/64"
    0.463"0.257"57588N260000
    M4 x 0.7 mm6.5 mmI
    6.9 mm3.200 mm107588N270000
    M5 x 0.8 mm8.25 mmN
    7.85 mm4.300 mm107588N280000
    M6 x 1 mm10.00 mm23/64"
    9.33 mm4.900 mm107588N2900000
    M8 x 1.25 mm11.75 mm29/64"
    11.75 mm6.800 mm107588N3100000
     
    18-8 Stainless Steel
    0-80
    0.125"48 Ga.
    0.078"0.050"107588N990000
    2-56
    0.125"9/64"
    0.142"0.072"257588N10100000
    4-40
    0.188"18 Ga.
    0.171"0.089"257588N10200000
    6-32
    0.219"7 Ga.
    0.202"0.110"257588N10300000
    8-32
    0.250"2 Ga.
    0.226"0.136"107588N1040000
    10-24
    0.281"F
    0.259"0.154"107588N1050000
    10-32
    0.281"F
    0.259"0.161"107588N1060000
    1/4"-20
    0.375"O
    0.321"0.204"107588N1070000
    5/16"-18
    0.469"Y
    0.404"0.261"57588N10800000
    3/8"-16
    0.562"29/64"
    0.466"0.318"57588N10900000
    M3 x 0.5 mm4.77 mm18 Ga.
    4.34 mm2.500 mm107588N1110000
    M4 x 0.7 mm6.35 mm2 Ga.
    5.74 mm3.400 mm107588N1120000
    M5 x 0.8 mm7.13 mmF
    6.57 mm4.300 mm107588N11300000
    M6 x 1 mm9.53 mmO
    8.15 mm5.100 mm107588N11400000
    M10 x 1.5 mm14.27 mm29/64"
    11.84 mm8.000 mm57588N11500000
     

    Closed-End Mold-In Threaded Inserts for Plastic

    Image of Product. Bottom orientation. Threaded Inserts. Closed-End Mold-In Threaded Inserts for Plastic.
    The closed end prevents molten plastic from seeping in and clogging the threads. Designed for injection molding, these inserts become inseparable from your part. They form a stronger bond than heat-set and press-fit inserts and last longer than threads cut directly into material. Unlike heat-set inserts, these work in a wide variety of plastics, including thermoset plastics that can’t be reformed.
    To install, position these inserts in your mold cavity with a core pin (not included).
    Brass—Conductive and nonmagnetic, these inserts are useful for electrical applications. They resist moisture but aren't as strong as steel inserts.
    Lightweight Aluminum—At one-third the weight of steel or brass, use these inserts in robotics, aerospace parts, and other applications with strict weight limits. They also resist rust about as well as stainless steel but aren't as strong. Since inserts are lead-free, they can be safely recycled.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals. Since they’re lead-free, they can be safely recycled.
    Thread Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    For Core
    Pin Dia.
    Pkg.
    Qty.
    Pkg.
    Brass
    2-56
    0.156"9/64"
    0.142"0.067"257588N3200000
    2-56
    0.219"9/64"
    0.142"0.067"257588N330000
    4-40
    0.205"18 Ga.
    0.171"0.089"107588N340000
    4-40
    0.281"18 Ga.
    0.171"0.089"107588N350000
    4-40
    0.344"18 Ga.
    0.171"0.089"107588N360000
    6-32
    0.250"7 Ga.
    0.202"0.104"257588N370000
    6-32
    0.344"7 Ga.
    0.202"0.104"257588N380000
    6-32
    0.469"7 Ga.
    0.202"0.104"107588N390000
    8-32
    0.469"2 Ga.
    0.226"0.130"107588N410000
    10-24
    0.438"F
    0.259"0.145"107588N420000
    10-24
    0.531"F
    0.259"0.145"107588N430000
    10-24
    0.750"F
    0.259"0.145"57588N440000
    10-32
    0.281"F
    0.259"0.156"107588N450000
    10-32
    0.438"F
    0.259"0.156"107588N460000
    10-32
    0.531"F
    0.259"0.156"107588N470000
    1/4"-20
    0.531"O
    0.321"0.196"107588N480000
    1/4"-20
    0.625"O
    0.321"0.196"107588N490000
    5/16"-18
    0.719"Y
    0.404"0.252"57588N510000
    3/8"-16
    0.812"29/64"
    0.466"0.307"57588N520000
    M2 x 0.4 mm4.75 mm30 Ga.
    3.38 mm1.700 mm257588N110000
    M3 x 0.5 mm5.21 mm18 Ga.
    4.34 mm2.500 mm257588N530000
    M3 x 0.5 mm8.74 mm18 Ga.
    4.34 mm2.500 mm107588N540000
    M4 x 0.7 mm11.91 mm2 Ga.
    5.74 mm3.200 mm57588N550000
    M5 x 0.8 mm13.49 mmF
    6.57 mm4.300 mm107588N560000
    M6 x 1 mm13.49 mmO
    8.15 mm4.900 mm107588N570000
    M6 x 1 mm15.88 mmO
    8.15 mm4.900 mm107588N580000
     
    Lightweight Aluminum
    8-32
    0.380"I
    0.272"0.136"257588N140000
    10-24
    0.459"N
    0.309"0.148"107588N150000
    1/4"-20
    0.610"23/64"
    0.367"0.200"107588N160000
    5/16"-18
    0.697"29/64"
    0.463"0.257"57588N170000
    M4 x 0.7 mm9.65 mmI
    6.9 mm3.200 mm257588N180000
    M5 x 0.8 mm11.65 mmN
    7.85 mm4.300 mm107588N190000
    M6 x 1 mm15.5 mm23/64"
    9.33 mm4.900 mm107588N210000
    M8 x 1.25 mm17.7 mm29/64"
    11.75 mm6.800 mm57588N220000
     
    18-8 Stainless Steel
    2-56
    0.156"9/64"
    0.142"0.072"107588N820000
    4-40
    0.205"18 Ga.
    0.171"0.089"107588N830000
    6-32
    0.250"7 Ga.
    0.202"0.110"107588N840000
    8-32
    0.250"2 Ga.
    0.226"0.136"107588N850000
    10-24
    0.531"F
    0.259"0.154"107588N860000
    10-32
    0.281"F
    0.259"0.161"107588N870000
    1/4"-20
    0.344"O
    0.321"0.204"107588N8800000
    5/16"-18
    0.594"Y
    0.404"0.261"57588N890000
    3/8"-16
    0.500"29/64"
    0.466"0.318"57588N910000
    M2.5 x 0.45 mm4.78 mm18 Ga.
    4.34 mm2.100 mm107588N920000
    M3 x 0.5 mm5.21 mm18 Ga.
    4.34 mm2.100 mm107588N930000
    M3.5 x 0.6 mm6.35 mm7 Ga.
    5.13 mm3.000 mm107588N940000
    M4 x 0.7 mm6.35 mm2 Ga.
    5.74 mm3.400 mm107588N950000
    M5 x 0.8 mm7.13 mmF
    6.57 mm4.300 mm107588N960000
    M6 x 1 mm8.73 mmO
    8.15 mm5.100 mm107588N9700000
    M8 x 1.25 mm11.13 mmY
    10.26 mm6.800 mm57588N980000
     

    Twist-Resistant Closed-End Mold-In Threaded Inserts for Plastic

    Image of Product. Bottom orientation. Threaded Inserts. Twist-Resistant Closed-End Mold-In Threaded Inserts for Plastic.
    Install threads that hold fast against twisting and pulling. These inserts have six ridged points for maximum contact and a more stable hold than other mold-in inserts. Since plastic flows into the knurls and ridges as inserts are molded in, they form a more durable bond than heat-set and press-fit inserts. You can even use them with phenolic and other thermoset plastics. Inserts have a closed end that prevents plastic from filling the threads during molding.
    To install, position these inserts in your mold cavity with a core pin (not included).
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals. Since they’re lead-free, they can be safely recycled.
    Thread Size
    Installed
    Lg.
    Drill Bit
    Size
    Overall
    Dia.
    For Core
    Pin Dia.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    8-32
    0.530"K
    0.52"0.130"107497N11000000
    10-24
    0.530"K
    0.52"0.145"107497N1200000
    10-32
    0.530"K
    0.52"0.156"57497N130000
    1/4"-20
    0.670"3/8"
    0.7"0.196"57497N1400000
    5/16"-18
    0.830"12 mm
    0.91"0.252"17497N150000
    3/8"-16
    0.960"14.5 mm
    1.04"0.307"17497N160000
    M4 x 0.7 mm13.5 mmK
    0.52"3.200 mm107497N1700000
    M5 x 0.8 mm13.5 mmK
    0.52"4.100 mm107497N1800000
    M6 x 1 mm17 mm3/8"
    0.7"4.900 mm57497N1900000
    M8 x 1.25 mm21 mm12 mm
    0.91"6.600 mm17497N210000
    M10 x 1.5 mm24.5 mm14.5 mm
    1.04"8.300 mm17497N220000
     
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