Add strong, reliable threads to thin materials with this 12-piece pack of 1/4 In.-20 steel threaded inserts. Finished in yellow zinc for added corrosion resistance, these rivet nuts work with metal, plastic, or fiberglass. Theyre designed for a grip range of .027 In. to .165 In. and install easily using threaded insert tool. Great for automotive, DIY, and light fabrication projects.