2.Professional manufactuer 3.ISO9001 passed 4.Exported Europe,North America,Mideast, South East Asia so on plastic package of core bits kitsCore bits --Professional quality 1.Ideal for cutting clean holes in concrete, brick&aerated block without steel 2.Material: carbide:YG8C,hardness:90 steel:45# 3. Service:15 meters 4.shank of sds-plus, sds max, hex and spline; 5.Pilot drill bit size: 8*100mm ( ...