Oslong Green Film 6-Inch PSA Sanding Disks Wet or Dry 10-Pack grits 40 - 600 (P180) Aluminum Oxide with Zirconia corundum Uniform Thickness and Surface Grit Greater Durability with Superior Anti-clogging technology Open coat, Zinc-stearated Unique and Proprietary Pressure-Sensitive Film Backing or Velcro for Critical Fine Sanding Outstanding, Long-lasting performance Wet or Dry