Shu Wen small countersunk head rivet nut with TSK, said Shu Wen blind rivet nuts small countersunk head with B-TSK said the country numerals are GB / T17880.3-1999. Rivet nuts, also called rivet nut, pull cap, pull the mother, Ram. Specifications M3-M12, there are British, American. Shu Wen small countersunk head rivet nut plate holes need to drill the hole, chamfer 90 °; pull cap wells than the outer diameter of the cylindrical 0.1-0.2mm; cylindrical roller patterns, non-slip effect; pull cap sink bevel inner plate holes, riveted plate and pull the cap back on a plane.