Expert for Concrete Long Life Diamond Grinding Head offers outstanding lifetime when grinding concrete. Double row of 18 segments ensures excellent endurance. High level of balance provides vibration-controlled work, which protects both users and the power tool. With 22.23 mm bore for concrete grinders and angle grinders with locking nut. Diameter mm: 115. Bore diameter mm: 22.23. Segment height mm: 5.0.