Add permanent metric threads to sheet metal, like weld nuts, but without the setup and mess. A zinc plating on these steel press-fit nuts provides corrosion resistance in wet environments. Also known as clinch-style captive nuts, press them into a drilled or punched hole with an arbor press or similar pressure tool. The pressure forms your sheet metal into the knurls of the nut, making the nut inseparable from the sheet. Installation requires access to both sides of the panel.