Aluminum oxide resin-bonded to a cloth backing. (Resin bond gives much longer life than glue bond.) Chatter-free operation for grinding, blending, deburring, smoothing, finishing and polishing flat and contoured metal surfaces. Long-lasting, top-quality bands. For hard metals, class rings, etc. Fits on Drum Arbors. Maximum operating speed: 30,000rpm. Available in 80 or 180 grit Measure 1/2" x 1/2". Sold in bags of 100.