nylon abrasive brush 1.Filament:Dupont TYNEX A silicon carbide 2.Nylon ... .grit load 30% 4 grit mesh:steel wire,36#--500# Abrasive Brush are used in marble, granite, limestone slate, sandstone, travertine ... # ,60#,80#coarse grinding120# ,180# ,240# rough polishing320 #,500# fine polishing abrasive nylon brush,polishing brush