This black-coloured, quick-change sanding disc is perfect for use in welding, metalworking, and in maintenance, repairs, and operations. It can be run wet or dry and is resin-bonded for heat resistance. This roll-on disc is three inches in diameter and has 80 grit aluminum oxide abrasive. It also has durable YF-weight polyester backing that is water-resistant. This sanding disc can withstand grinding speeds up to 20,000 RPM.