Features: Rivet nuts are made from aluminum alloy which provides strength, corrosion protection and long service life. With open end, small flange, round hole, threaded inner wall and partial anti-skid surface, these flat head rivet nut has a good performance of fastener function. There are various sizes, M3, M4, M5, M6, M8 and they normally have low profile compared to other nuts. Each size includes many pieces of rivet nuts so you don't have to go to hardware store searching rivet nuts for a while. Comes with a rivet gun and many mandrels and nosepieces for convenient riveting.Specifications: Rivet Nut Material: Aluminum alloy Type: Flat head rivet nut Nut Thread Size: M3, M4, M5, M6, M8 Rivet Gun Size: 9.7*27cm/3.82*10.63inPackage Includes: 20pcs x M3 Rivet Nuts20pcs x M4 Rivet Nuts20pcs x M5 Rivet Nuts10pcs x M6 Rivet Nuts10pcs x M8 Rivet Nuts5pcs x Mandrels and Nosepieces(M3, M4, M5, M6, M8)1pc x Rivet Gun .