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.

HFG8 and HF109 (heavy-duty high tensile strength) Studs are manufactured for the most demanding applications from medium carbon alloy steel, then heat-treated to high strength and hardness qualities.
  • Types HFG8 and HF109 are for heavy-duty applications in sheets as thin as .040”.
  • Grade 8 and property class 10.9 studs meeting 150 ksi/1040 MPa minimum.
  • Recommended for use in steel or HSLA steel sheets HRB (Rockwell “B” Scale) 89 or less and HB (Hardness Brinell) 180 or less.
  • Large head diameter spreads compressive stress on panel.
To be sure that you are getting genuine PEM products, look for the PEM stamp. Studs within the size range of the SAE and ISO specs are also identified with the Grade 8 and 10.9 head markings respectively.

Thread size #10-32 does not have SAE head marking since it is technically not within the size range of the specification.
Unit of Measure


Thread Size

N/A 0.250-20 (1/4-20)

Thread Code

N/A 0420

Length Code

N/A 16

Min. Sheet Thickness

N/A 0.040 in

Hole Size in Sheet + .005 - .000

N/A 0.250 in

Max. Hole in Attached Parts

N/A 0.340 in
L - Length ± .0151
N/A 01.00 in a-1379.jpg

H ± 0.01

N/A 0.507 in

S Max.

N/A 0.125 in

T Max.

N/A 0.090 in

Min. Dist. Hole C/L to Edge

N/A 0.709 in

For Use in Sheet Hardness

N/A HRB 89/HB 180 or Less

Thread Specification

N/A External, ANSI B1.1, 2A

Fastener Material

N/A Heat-Treated Medium Carbon Alloy Steel

Standard Finish

N/A Zinc Plated, 5µm, Colorless

CAD Supplier

N/A PennEngineering® (PEM®)

On Hand

N/A {0}
  • 1 Other lengths available up to a maximum of 1.5" (unified) on special order.