1,Rivet nuts are made from aluminum alloy which provides strength, corrosion protection and long service life 2,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 3,There are various sizes, M3, M4, M5, M6, M8 and they normally have low profile compared to other nuts 4,Each size includes many pieces of rivet nuts so you don't have to go to hardware store searching rivet nuts for a while 5,Comes with a rivet gun and many mandrels and nosepieces for convenient riveting 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 Weight: 1kg(approx.) Package Includes: 20pcs x M3 Rivet Nuts 20pcs x M4 Rivet Nuts 20pcs x M5 Rivet Nuts 20pcs x M6 Rivet Nuts 20pcs x M8 Rivet Nuts 5pcs x Mandrels (M3, M4, M5, M6, M8) 5pcs x Nosepieces (M3, M4, M5, M6, M8) 1 x Rivet Gun 1 x User Manual Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.