182N Series 2 T-A Original Drill Inserts Hss Premium Cobalt TiCN Coated The T-A drilling system is a Universal replaceable spade insert drilling system.With constant innovations in holder designs, insert geometries and coatings, and coolant dispersion, the T-A drilling system continues to evolve and become much more productive and powerful than ever beforeHSS Premium Cobalt -Suited for rigid machining applications, used for drilling exotic and high alloy materials, or general use when surface speed needs to be increased. For material hardness up to 400 BHN 139kgTiCN Coating Excellent choice for wear resistance over low surface speeds High hardness/wear resistance Maximum working temperature 400C Hardness HV 3500 Colour: blue/greyNOTE:2.5 series inserts fit into both 2 and 2.5 series holders. However, 2 series inserts ONLY fit into 2 series holder