Zirconium abrasive flaps are layered onto a depressed-center fiberglass disc. As the abrasive flaps wear, New, sharp abrasive grain is constantly being exposed providing a constant finish through the life of the disc. Flap Disc design offers time-saving alternative to resin Fiber Discs. Multiple applications from rough metal removal to finishing of ferrous and nonferrous metals including stainless steel. Bulk packed. Type 29.