THREADING CLASSIFICATION (INTERNAL THREADING) Name of Tool Holder Insert Shape Features MMTI a Minimum cutting diameter .500 inch.a Various insert types. Boring Bars a Precision class insert for precise thread forms. a Available with a pressed breaker for chip control. a Able to change lead angle by replacing the shim. ^ G026 FSL5 a Screw-on type.a Precision class insert. S-SL5 a Holder is capable of performing both grooving and threading. Boring Bars a Maximum groove depth .118 inch. ^ G031 ^ G032 MICRO-MINI TWIN a Solid carbide type. Boring Bars a Economical due to single holder with two cutting edges. ─ G ^ G034 MICRO-MINI a Solid carbide type. Boring Bars a Insert can be ground to suit the application. ─ ^ E031 G003