The BROACH for polygonal holes is a specially shaped tool that is fixed to the boring bar of the broacher on one end, while the other end bears the shape of the hole to be formed. The broaches making up this family are manufactured from special HSS steel, duly treated so that they can also be used to machine hard materials. The broaches are available in three size ranges, classified according to the diameter of the shank coupling the broach to the broacher.