Arc Abrasives 31713 Type R Zirconia Alumina Quick-Lok Discs, 60 Grit, 1-1/2-Inch Diameter, 100-Pack 1-1/2 Inch in diameter Performance Coating alleviates heat from the grinding process so discs won't load with aluminum or other soft metals Compact grains that have multiple layers of the same grit Less loading, longer life and consistent finish Pack of 100 discs