... '',5'',6'', 7'' 2. Grain: 40#-320# Flap disc, flap wheel/ abrasives disc/abrasives polishing disc /mop disc/1. Diameter: 4'',5'',6'', 7''2. Grain ... SANDING PAPER , NORTON SANDING PAPER , DOMESTIC SANDING PAPER6. Backing support : SBS PLASTIC BACKING ,FIBERGLASS PACKINGiTIS GOOD FOR CLEANING OF WELDING SEAMS , DE ...