Diameter 2″. Coarse. Built for consistency in blending, cleaning, deburring, finishing, grinding, polishing, radiusing, refining, and surface preparation, depending on the chosen grade. Springy nonwoven fibers resist loading, conform to irregular or contoured surfaces, and minimize undercutting and gouging. Convenient 3M Roloc Attachment System allows for fast disc changes. Abrasive material: Aluminum Oxide. Attachment type: TR. Backing material: Non-woven. Sold 25 discs per box.