... 3)Type:X,XX,EX,EXX,EC,ECC,ESF,ESSF,ESD,ESSD,EY,EYY Dingrun High Quality Self-drilling Anchor Drill ... ESSF Tungsten carbide button drill bit Φ51 Φ76 Φ100 Φ120 ESD Cast/hardened button drill bit Φ115 ESSD Tungsten carbide button ... Φ76 Φ76/90 General Introduction Jiangyin Dingrun Precision Steel Tube Co. Ltd. (JYDR) is one of the leading manufacturers, exporters and importers ...