Grobet Swiss Pattern File Inox Halfround 6 Inch Cut 2 For platinum, stainless steel, exotic plastics, and other hard to file materials. The hardest surface known -Rockwell hardness 72HRc. Better performance on hard-to-file surfaces. Little or no clogging; a simple knock is enough to remove the chips. Highly resistant to corrosion. Longer life than standard files. Swiss Pattern files means a type of fine file used for precision filing of jewelry, instrument parts, and dies. It does not necessarily mean that all Swiss Pattern files are Swiss made. Used by Professionals