... performance, close tolerance, long service, various material choices. 1.quality pilot punch: Material:SKH-51,ASP-23,ASP-60,SKD-11 ... myriad identifying marks whether you refer to tungsten carbide punches, pilot punches, piercing punches, dowel pins,punch guide bush,extrusion punches ... in our products,Welcomed to visit our factory or send e-mail or call me at your convenience. We are all ...