Scratch brush 1.Applying to grind elbowboard,countertop,column and arc slab. 2.Female screw: 5/8"-11 , M14, M16 Scratch brush1.Product information 1.Steel wire circle brush with screw 2.Applying to grind elbowboard,countertop,column and arc slab.3.Screwed hole: 5/8"-11 , M14, M164.Filament diameter: 0.6mm-0.8mm5.Packing(pcs/ctn): 36/48