A rivet nut also known as a blind nut or nut-sert, is a one-piece internally threaded and counter bored tubular rivet that can be anchored entirely from one side. There are two types; one is designed to form a bulge on the back side of the panel as a screw is tightened in its thread. They provide thread into thin sheet material; rivet nuts provide an internal thread, bolts an external thread. At the same time they can also function as a blind fastener to join two materials together