Diablo Universal 12-Hole Hook and Lock Vented Sanding Disc Premium universal 12-hole ROS random orbital sanding discs with Hook Lock backing include break-through innovations that improve performance, extend sanding life and increase productivity. Featuring a premium ceramic blend, these discs remove material faster than other sanding discs and offer an extra long sanding life. Clog-SHIELD grinding agent reduces loading, thus maximizing productivity. The superior grain bonding system, ENDURA-BOND provides these discs with longer life and extreme durability. Fits all 5 and 8 hole sanders. Diameter 5 , Grit 40-Grit, Abrasive Material Ceramic Blend, Backing Type Hook Lock, Pkg Qty 50, Package Type Card