Type HFG8 (unified) and Type HF109 (metric) heat-treated carbon-alloy steel clinch studs install permanently in carbon-steel or HSLA-steel sheets as thin as 0.040 in. They studs have tensile strengths of at least 150 ksi. Large-diameter heads transmit less compressive stress to panels.
The studs come in in thread sizes up to 5/16-18 and in lengths up to 1 in. Longer lengths can be specially ordered.  Appropriate sizes meet SAE J429 and ISO 898-1/SAE J1199 specifications, and all the studs are RoHS compliant.

PennEngineering, 5190 Old Easton Rd., Danboro, PA 18916, (800)237-4736, www.pemnet.com