PEM® self-clinching studs are installed by placing them in properly sized holes in the sheets and squeezing into place with any standard press. The squeezing action embeds the head of the stud into the sheet. The metal displaced by the head flows smoothly and evenly around the ribs and into the annular groove - creating a flushhead assembly and securely locking the stud into the sheet with high torque-out and pushout resistances.

HFE (heavy-duty) Studs are designed with an enlarged head diameter which projects above the sheet material and provides maximum pull through in sheets as thin as .040”.
  • Enlarged head diameter provides high-strength in sheets as thin as .040”.
  • Recommended for use in steel or aluminum sheets HRB (Rockwell “B” Scale) 85 or less and HB (Hardness Brinell) 165 or less.
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Unit of Measure

Thread Size

 .250-20 (1/4-20)

Thread Code

 0420

Length Code

 8
Min. Sheet Thickness1 .040 in

Hole Size in Sheet + .005 - .000

 .250 in

L - Length ± .015

 .500 in
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H ± .01

 .462 in
S Max.2 .118 in

T Max.

 .060 in

Max. Hole in Attached Parts

 .340 in

Min. Dist. Hole C/L to Edge

 .470 in

Thread Strength

 120 ksi

For Use in Sheet Hardness

 HRB 85 / HB 165 or Less

Thread Specification

 External, ANSI B1.1, 2A

Fastener Material

 Heat-Treated Carbon Steel

Standard Finish

 Zinc plated per ASTM B633, SC1 (5µm), Type III, colorless

CAD Supplier

 PennEngineering® (PEM®)
  • 1 For maximum performance, we recommend that you use the maximum shank length for your sheet thickness.
  • 2 Threads are gageable to within 2 pitches of the “S” Max. dimension. A class 3B/5H maximum material commercial nut shall pass up to the “S” Max. dimension.