1.cutting hard material,such as stone,granite 2.very good performance 3.peed very fast,with chip out when working core drill bit kitmodel number DBSET01Comprising:3-pcs core drill: 52X150MM, 65X150MM, 117X150MM4 Accessories:Hex adaptor 90mm, pilot drill 8X200mm,extension 200mm,SDS-plus adaptor 115mm, drift key,with a alumnium case has some other box core drill bit kit