Nikcole SET 5 Mini-Groove Kit, 1/2" Shank toolholder plus 5 coated carbide grooving inserts .035-.073" Set of 1/2" Sq RH Holder plus 5 inserts. Inserts are .9mm, 1.1mm, 1.3mm, 1.6mm, 1.85mm Grade C6PV TiN coated inserts. Includes Key and spare screw.