Pressure Sensitive Adhesive Backed F-Weight Disc. For Use On Wood, Metal, Fiberglass, And Painted Surfaces. Peel Off Paper And Press Disc To Back-Up Pad. Includes: (5) 60 Grit, (5) 100 Grit, (5) 150 Grit. These Are Complete Line Of Heavy-Duty Shop Products That Will Bring You Years Of Reliable Performance.