... head half hex rivet nut specification: M5 Material:Stainless Steel. stainless steel blind flat head half hex rivet nutspecification: M4-M12type: 1. ... : flat head ,countersunk head, round body, hex body, open end, closed end, body with ribben, body with groove and so on . also ... /32 3/16,1/4,5/16,3/8 . material: steel, stainless steel, brass,aluminium Stainless Steel Closed end Rivet Nut