6.4 mm 0.030 0.250 Projection 0.76 mm Minimum Bore Diameter 0.100 0.1875 Maximum Bore Depth 0.76 mm Groove Width 0.030 Solid Carbide Tool AlTiN Coated Micro 100 QMFR-030-250-100X Quick Change Miniature Full Radius Grooving Tool 2.54 mm