BP200 BPG20B Carbide Insert:

Parting inserts are indexable tool bits used to cut off a piece of the workpiece while grooving inserts are used to make a recess, undercut, or neck in the workpiece. These inserts are mounted in a compatible tool holder or cut-off blade in a lathe or CNC and are intended to be replaced once dull to maintain the quality of your workmanship. Parting and grooving inserts are usually made from carbide steel and are available in different sizes.