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.

HFH (heavy-duty) Studs replace weld studs with easier installation at lower costs. The large stud head which projects above the sheet material distributes the axial tightening force over a large area thereby improving pull through resistance.

HFHB (heavy-duty BUSBAR®) Studs are ideal for applications which demand superior electrical/mechanical attachment points. Phosphor bronze studs offer twice the conductivity of carbon steel studs.
  • Types HFH and HFHS are for high-strength applications in sheets as thin as .050”.
  • Type HFHB is for superior electrical/mechanical
  • more
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Unit of Measure

Thread Size

.250-20 (1/4-20)

Thread Code

0420

Length Code

8
Min. Sheet Thickness1 .060 in

Hole Size in Sheet + .005 - .000

.250 in

Max. Hole in Attached Parts

.312 in

L - Length ± .015

.500 in
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H ± .01

.380 in
S Max.2 .125 in

T Max.

.050 in

Min. Dist. Hole C/L to Edge

.460 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.