A blind rivet is a low-cost permanent fastening system designed to join two or more pieces of material together where only one side is accessible. The term ‘blind rivets” comes from the fact that you are unable to see the other side. A blind rivet nut, also known as a rivet nut, nut-sert or riv-nut, is a one-piece internally threaded and counterbored tubular rivet, used to create highly durable threads particularly in thin materials where only one side is accessible