Toolzone 115mm (4-1/2″) Mortar Raking Angle Grinder Disc115mm (4-1/2″) mortar raking disc.Designed for the removal of mortar from joints without damaging masonry.115mm (4-1/2″) diameter disc with 22.2mm centre bore hole.Can outlast up to 200 abrasive discs – average life 300 square meters of brick work.Max operating speed: 13,200rpm.