Trend DWS/NFPK/F Fine Diamond Needle Files Consisting of Flat, Half Round/Taper/Flat, Triangular/Taper, Round/Taper, 4-Pack Pack is comprised of four diamond needle files: tapered/round, taper half flat/round, round/flat and triangular/tapered Diamond files are 160mm in length and have 75mm diamond coverage and they have a flashed silver handle Trend diamond files can be used on carbide, HSS, metals and plastics Trend diamond needle files are used in British Aerospace Industry Also widely used in Jewelry making industry