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    172 Products
    About Threaded Inserts
    industrial info icon

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

    Performance

    Performance

    Screw-to-Expand Press-In Threaded Inserts for Plastic

    Press these inserts into a drilled hole, then install a screw to expand them. Inserts won't lose their strength as you remove and reinsert screws during inspection or repair. The sharp diamond knurls dig into the surrounding material for a stronger hold than other press-in inserts for plastic. Install inserts with an arbor press or similar pressure tool.
    Flanged Profile—Flanges on the insert create a load-bearing surface that prevents cracks or deformation in the base material. They also curb overtightening and keep inserts from getting pulled out or through.
    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.
    Flange
    Thread Size
    Installed
    Lg.
    Dia.
    Thick.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Pkg.
    Qty.
    Pkg.
    Standard Profile
    Image of Product. Bottom orientation. Threaded Inserts. Screw-to-Expand Press-In Threaded Inserts for Plastic, Standard Profile.
     
    Brass
    0-80
    		0.125"——3/32"
    		0.094"2500000000000000
    2-56
    		0.156"——1/8"
    		0.125"5000000000000000
    4-40
    		0.188"——5/32"
    		0.156"5000000000000000
    4-40
    		0.250"——5/32"
    		0.156"250000000000000
    6-32
    		0.250"——3/16"
    		0.188"5000000000000000
    6-32
    		0.313"——3/16"
    		0.188"250000000000000
    8-32
    		0.250"——7/32"
    		0.219"250000000000000
    8-32
    		0.313"——7/32"
    		0.219"5000000000000000
    10-24
    		0.375"——1/4"
    		0.250"250000000000000
    10-32
    		0.250"——1/4"
    		0.250"250000000000000
    10-32
    		0.375"——1/4"
    		0.250"250000000000000
    1/4"-20
    		0.438"——5/16"
    		0.313"250000000000000
    1/4"-20
    		0.500"——5/16"
    		0.313"250000000000000
    5/16"-18
    		0.563"——3/8"
    		0.375"100000000000000
    3/8"-16
    		0.625"——7/16"
    		0.438"100000000000000
    M2 x 0.4 mm4 mm——3.2 mm
    		3.2 mm100000000000000
    M2.5 x 0.45 mm4.8 mm——4 mm
    		4 mm100000000000000
    M3 x 0.5 mm4.8 mm——4 mm
    		4 mm5000000000000000
    M3 x 0.5 mm6.4 mm——4 mm
    		4 mm250000000000000
    M3.5 x 0.6 mm6.4 mm——4.8 mm
    		4.8 mm5000000000000000
    M4 x 0.7 mm6.4 mm——5.6 mm
    		5.6 mm250000000000000
    M4 x 0.7 mm8 mm——5.6 mm
    		5.6 mm250000000000000
    M5 x 0.8 mm8 mm——6.4 mm
    		6.4 mm2500000000000000
    M5 x 0.8 mm9.5 mm——6.4 mm
    		6.4 mm250000000000000
    M6 x 1 mm11.1 mm——8 mm
    		8 mm2500000000000000
    M6 x 1 mm12.7 mm——8 mm
    		8 mm2500000000000000
    M8 x 1.25 mm12.7 mm——9.5 mm
    		9.5 mm10000000000000
     
    Lightweight Aluminum
    2-56
    		0.156"——1/8"
    		0.125"250000000000000
    4-40
    		0.188"——5/32"
    		0.156"250000000000000
    4-40
    		0.250"——5/32"
    		0.156"250000000000000
    6-32
    		0.250"——3/16"
    		0.188"250000000000000
    6-32
    		0.313"——3/16"
    		0.188"250000000000000
    8-32
    		0.250"——7/32"
    		0.219"250000000000000
    8-32
    		0.313"——7/32"
    		0.219"250000000000000
    10-24
    		0.375"——1/4"
    		0.250"2500000000000000
    10-32
    		0.313"——1/4"
    		0.250"250000000000000
    10-32
    		0.375"——1/4"
    		0.250"2500000000000000
    1/4"-20
    		0.438"——5/16"
    		0.313"2500000000000000
    1/4"-20
    		0.500"——5/16"
    		0.313"2500000000000000
    5/16"-18
    		0.563"——3/8"
    		0.375"100000000000000
    3/8"-16
    		0.625"——7/16"
    		0.438"100000000000000
    M3 x 0.5 mm4.8 mm——4 mm
    		4 mm250000000000000
    M3 x 0.5 mm6.4 mm——4 mm
    		4 mm250000000000000
    M4 x 0.7 mm6.4 mm——5.6 mm
    		5.6 mm250000000000000
    M4 x 0.7 mm8 mm——5.6 mm
    		5.6 mm250000000000000
    M5 x 0.8 mm8 mm——6.4 mm
    		6.4 mm250000000000000
    M5 x 0.8 mm9.5 mm——6.4 mm
    		6.4 mm2500000000000000
    M6 x 1 mm11.1 mm——8 mm
    		8 mm2500000000000000
    M6 x 1 mm12.7 mm——8 mm
    		8 mm2500000000000000
    M8 x 1.25 mm14.3 mm——9.5 mm
    		9.5 mm100000000000000
    M10 x 1.5 mm15.88 mm——11.1 mm
    		11.1 mm100000000000000
     
    18-8 Stainless Steel
    2-56
    		0.156"——1/8"
    		0.125"100000000000000
    4-40
    		0.188"——5/32"
    		0.156"1000000000000000
    6-32
    		0.250"——3/16"
    		0.188"1000000000000000
    8-32
    		0.250"——7/32"
    		0.219"50000000000000
    8-32
    		0.313"——7/32"
    		0.219"50000000000000
    10-24
    		0.375"——1/4"
    		0.250"50000000000000
    10-32
    		0.250"——1/4"
    		0.250"50000000000000
    10-32
    		0.375"——1/4"
    		0.250"500000000000000
    1/4"-20
    		0.500"——5/16"
    		0.313"500000000000000
    5/16"-18
    		0.563"——3/8"
    		0.375"500000000000000
    3/8"-16
    		0.625"——7/16"
    		0.438"10000000000000
    M3 x 0.5 mm4.8 mm——4 mm
    		4 mm50000000000000
    M4 x 0.7 mm8 mm——5.6 mm
    		5.6 mm50000000000000
    M5 x 0.8 mm9.5 mm——6.4 mm
    		6.4 mm50000000000000
    M6 x 1 mm12.7 mm——8 mm
    		8 mm10000000000000
    M8 x 1.25 mm12.7 mm——9.5 mm
    		9.5 mm50000000000000
     
    Flanged Profile
    Image of Product. Bottom orientation. Threaded Inserts. Screw-to-Expand Press-In Threaded Inserts for Plastic, Flanged Profile.
     
    Brass
    2-56
    		0.156"0.187"0.02"1/8"
    		0.125"5000000000000000
    4-40
    		0.188"0.218"0.02"5/32"
    		0.156"5000000000000000
    4-40
    		0.250"0.218"0.02"5/32"
    		0.156"250000000000000
    6-32
    		0.250"0.249"0.03"3/16"
    		0.188"5000000000000000
    6-32
    		0.281"1/4"0.03"3/16"
    		0.188"100000000000000
    8-32
    		0.281"0.28"0.03"7/32"
    		0.219"250000000000000
    8-32
    		0.313"0.28"0.03"7/32"
    		0.219"5000000000000000
    10-32
    		0.313"0.312"0.04"1/4"
    		0.250"2500000000000000
    10-32
    		0.375"0.312"0.04"1/4"
    		0.250"250000000000000
    1/4"-20
    		0.438"3/8"0.05"5/16"
    		0.313"100000000000000
    1/4"-20
    		0.500"3/8"0.05"5/16"
    		0.313"2500000000000000
    5/16"-18
    		0.563"0.437"0.05"3/8"
    		0.375"100000000000000
    3/8"-16
    		0.625"1/2"0.06"7/16"
    		0.438"100000000000000
    M3 x 0.5 mm4.8 mm5.5 mm0.51 mm4 mm
    		4 mm5000000000000000
    M3 x 0.5 mm6.3 mm5.5 mm0.51 mm4 mm
    		4 mm250000000000000
    M4 x 0.7 mm7.1 mm7.1 mm0.81 mm5.6 mm
    		5.6 mm250000000000000
    M4 x 0.7 mm8 mm7.1 mm0.81 mm5.6 mm
    		5.6 mm5000000000000000
    M5 x 0.8 mm7.9 mm7.9 mm1.09 mm6.4 mm
    		6.4 mm100000000000000
    M5 x 0.8 mm9.5 mm7.9 mm0.99 mm6.4 mm
    		6.4 mm250000000000000
    M6 x 1 mm11.1 mm9.5 mm1.27 mm8 mm
    		8 mm100000000000000
    M6 x 1 mm12.7 mm9.5 mm1.25 mm8 mm
    		8 mm250000000000000
    M8 x 1.25 mm14.3 mm11.1 mm1.25 mm9.5 mm
    		9.5 mm100000000000000
     
    Lightweight Aluminum
    2-56
    		0.156"3/16"0.02"1/8"
    		0.125"2500000000000000
    4-40
    		0.186"7/32"0.02"5/32"
    		0.156"2500000000000000
    4-40
    		0.248"7/32"0.02"5/32"
    		0.156"2500000000000000
    6-32
    		0.252"1/4"0.03"3/16"
    		0.188"2500000000000000
    6-32
    		0.283"1/4"0.03"3/16"
    		0.188"2500000000000000
    8-32
    		0.286"9/32"0.04"7/32"
    		0.219"2500000000000000
    8-32
    		0.318"9/32"0.04"7/32"
    		0.219"2500000000000000
    10-24
    		0.375"5/16"0.03"1/4"
    		0.250"100000000000000
    10-32
    		0.310"5/16"0.04"1/4"
    		0.250"2500000000000000
    10-32
    		0.372"5/16"0.04"1/4"
    		0.250"2500000000000000
    1/4"-20
    		0.438"3/8"0.05"5/16"
    		0.313"2000000000000000
    1/4"-20
    		0.500"3/8"0.05"5/16"
    		0.313"2000000000000000
    5/16"-18
    		0.563"7/16"0.03"3/8"
    		0.375"1000000000000000
    3/8"-16
    		0.625"1/2"0.03"7/16"
    		0.438"1000000000000000
    M3 x 0.5 mm4.78 mm5.6 mm0.56 mm4 mm
    		4 mm2500000000000000
    M3 x 0.5 mm6.36 mm5.6 mm0.56 mm4 mm
    		4 mm2500000000000000
    M4 x 0.7 mm7.14 mm7.1 mm0.89 mm5.6 mm
    		5.6 mm2500000000000000
    M4 x 0.7 mm7.95 mm7.1 mm0.89 mm5.6 mm
    		5.6 mm2500000000000000
    M5 x 0.8 mm7.95 mm8 mm1.09 mm6.4 mm
    		6.4 mm2500000000000000
    M5 x 0.8 mm9.52 mm8 mm1.09 mm6.4 mm
    		6.4 mm2500000000000000
    M6 x 1 mm11.13 mm9.5 mm1.27 mm8 mm
    		8 mm2500000000000000
    M6 x 1 mm12.7 mm9.5 mm1.27 mm8 mm
    		8 mm2500000000000000
    M8 x 1.25 mm14.3 mm11.1 mm0.76 mm9.5 mm
    		9.5 mm1000000000000000
    M10 x 1.5 mm15.88 mm12.7 mm0.76 mm11.1 mm
    		11.1 mm1000000000000000
     
    18-8 Stainless Steel
    2-56
    		0.156"0.187"0.02"1/8"
    		0.125"1000000000000000
    4-40
    		0.188"0.218"0.02"5/32"
    		0.156"1000000000000000
    6-32
    		0.250"0.249"0.02"3/16"
    		0.188"1000000000000000
    8-32
    		0.313"0.28"0.02"7/32"
    		0.219"50000000000000
    10-32
    		0.375"0.312"0.03"1/4"
    		0.250"500000000000000
    1/4"-20
    		0.500"3/8"0.03"5/16"
    		0.313"500000000000000
    5/16"-18
    		0.563"0.437"0.06"3/8"
    		0.375"500000000000000
    3/8"-16
    		0.625"1/2"0.06"15/32"
    		0.469"500000000000000
    M3 x 0.5 mm4.8 mm5.5 mm0.51 mm4 mm
    		4 mm50000000000000
    M4 x 0.7 mm8 mm7.1 mm0.81 mm5.6 mm
    		5.6 mm50000000000000
    M5 x 0.8 mm9.5 mm7.9 mm0.99 mm6.4 mm
    		6.4 mm50000000000000
    M6 x 1 mm12.7 mm9.5 mm1.25 mm8 mm
    		8 mm10000000000000
    M8 x 1.25 mm14.3 mm11.1 mm1.52 mm9.9 mm
    		9.9 mm500000000000000
     

    Screw-to-Expand Press-In Threaded Inserts For Through Holes in Plastic

    Image of Product. Bottom orientation. Threaded Inserts. Screw-to-Expand Press-In Threaded Inserts For Through Holes in Plastic.
    Press these inserts into a through hole from the underside of your material, and the flange keeps them from going too far. Then, thread in a screw to expand the insert, driving the sharp diamond knurls into the plastic. Install using an arbor press or similar pressure tool. Installed length includes the flange.
    Brass—Conductive and nonmagnetic, these inserts are useful for electrical applications. They resist moisture but aren't as strong as steel inserts.
    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.
    Flange
    Thread Size
    Installed
    Lg.
    Dia.
    Thick.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Pkg.
    Qty.
    Pkg.
    Brass
    2-56
    		0.156"0.187"0.02"1/8"
    		0.125"2500000000000000
    4-40
    		0.188"0.218"0.02"5/32"
    		0.156"250000000000000
    6-32
    		0.250"0.249"0.03"3/16"
    		0.188"250000000000000
    8-32
    		0.313"0.28"0.03"7/32"
    		0.219"250000000000000
    10-32
    		0.375"0.312"0.04"1/4"
    		0.250"2500000000000000
    1/4"-20
    		0.500"3/8"0.05"5/16"
    		0.313"2500000000000000
    M2 x 0.4 mm4 mm4.8 mm0.5 mm3.2 mm
    		3.2 mm2500000000000000
    M2.5 x 0.45 mm4.8 mm5.6 mm0.55 mm4 mm
    		4 mm2500000000000000
    M3 x 0.5 mm4.8 mm5.6 mm0.55 mm4 mm
    		4 mm2500000000000000
    M4 x 0.7 mm8 mm7.2 mm0.85 mm5.6 mm
    		5.6 mm100000000000000
    M5 x 0.8 mm9.5 mm8 mm1 mm6.4 mm
    		6.4 mm100000000000000
    M6 x 1 mm12.7 mm9.5 mm1.3 mm8 mm
    		8 mm1000000000000000
    M8 x 1.25 mm12.7 mm11 mm1.3 mm9.6 mm
    		9.6 mm1000000000000000
     
    18-8 Stainless Steel
    2-56
    		0.156"0.187"0.02"1/8"
    		0.125"1000000000000000
    4-40
    		0.188"0.218"0.02"5/32"
    		0.156"1000000000000000
    6-32
    		0.250"0.249"0.03"3/16"
    		0.188"1000000000000000
    8-32
    		0.313"0.28"0.03"7/32"
    		0.219"1000000000000000
    10-32
    		0.375"0.312"0.04"1/4"
    		0.250"50000000000000
    1/4"-20
    		0.500"3/8"0.05"5/16"
    		0.313"50000000000000
    M2 x 0.4 mm4 mm4.8 mm0.43 mm3.2 mm
    		3.2 mm50000000000000
    M2.5 x 0.45 mm4.8 mm5.5 mm0.51 mm4 mm
    		4 mm50000000000000
    M3 x 0.5 mm4.8 mm5.5 mm0.51 mm4 mm
    		4 mm50000000000000
    M4 x 0.7 mm8 mm7.1 mm0.81 mm5.6 mm
    		5.6 mm50000000000000
    M5 x 0.8 mm9.5 mm7.9 mm1 mm6.4 mm
    		6.4 mm50000000000000
    M6 x 1 mm12.7 mm9.5 mm1.24 mm8 mm
    		8 mm50000000000000
    M8 x 1.25 mm12.7 mm11.1 mm1.52 mm9.6 mm
    		9.6 mm500000000000000
     

    Strong-Grip Screw-to-Expand Press-In Threaded Inserts for Plastic

    Image of Product. Bottom orientation. Threaded Inserts. Strong-Grip Screw-to-Expand Press-In Threaded Inserts for Plastic.
    For a more secure hold than other screw-to-expand inserts, fins cut into the surrounding plastic. Press or hammer these inserts into a drilled hole and then install a screw to expand the fins.
    Brass—Conductive and nonmagnetic, these inserts are useful for electrical applications. They resist moisture but aren't as strong as steel inserts.
    Thread Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of
    Fins
    Pkg.
    Qty.
    Pkg.
    Standard Profile
     
    Brass
    4-40
    		0.188"5 Ga.
    		0.206"125000000000000000
    4-40
    		0.375"5 Ga.
    		0.206"22500000000000000
    6-32
    		0.188"5 Ga.
    		0.206"1250000000000000
    6-32
    		0.375"5 Ga.
    		0.206"22500000000000000
    8-32
    		0.188"15/64"
    		0.234"1250000000000000
    8-32
    		0.375"15/64"
    		0.234"22500000000000000
    10-24
    		0.375"G
    		0.261"22500000000000000
    10-32
    		0.188"G
    		0.261"12500000000000000
    10-32
    		0.375"G
    		0.261"22500000000000000
    10-32
    		0.563"11/32"
    		0.344"3100000000000000
    1/4"-20
    		0.375"21/64"
    		0.328"22500000000000000
    1/4"-20
    		0.563"13/32"
    		0.406"31000000000000000
    5/16"-18
    		0.563"15/32"
    		0.469"350000000000000
    M2 x 0.4 mm4 mm3.2 mm
    		3.2 mm4100000000000000
    M2.5 x 0.45 mm4.8 mm4 mm
    		4 mm4100000000000000
    M3 x 0.5 mm4.8 mm4 mm
    		4 mm5100000000000000
    M4 x 0.7 mm8 mm5.6 mm
    		5.6 mm5100000000000000
    M5 x 0.8 mm9.5 mm6.6 mm
    		6.6 mm22500000000000000
    M6 x 1 mm9.5 mm8.3 mm
    		8.3 mm22500000000000000
    M8 x 1.25 mm14.3 mm11.9 mm
    		11.9 mm350000000000000
     
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