High quality rivet nuts  made of zinc plated steel and to AN 322 standards. 

Application 

Blind rivet nuts can be installed into sheet-metal, tubing, plastics and other materials to provide strong, reliable internal threads in applications that require subsequent component assembly. 

Flat head provides a good bearing area for application surface and for bolted-on part Hexagonal shank used in conjunction with a hexagon hole to give maximum resistance to applied torque or unscrewing torque