CCMT-32.51-HM 80 Degree Diamond +Rake Insert ~ HM - with a sharp wave cutting edge to reduce cutting force, it is the first choice for semi-finishing of internal holes and allows chips to flow smoothly. ~ XAB749: Cutting edge with special strength and toughness, in an optimal combination with MT-TiCN, thick layer Al2O3TiN coating. ~ It is a suitable grade for a wide number of applications. ~ It is good for finishing, semi-finishing and light roughing of steel, cast steel and stainless steel. ~ ISO Insert No. CCMT09T304HM ~ I.C. is 3/8" ~ L is 3/8" ~ S is 5/32" ~ d is .017" ~ r is .0157".