The Eastwood Contour SCT® Abrasive Flap Sanding Drum is to be used for paint or rust removal applications, while metal conditioning at the same time. Each drum is 4 inches wide and 4.5 inches in diameter. Aluminum Oxide Abrasive Drum with ABS Plastic Hub 60 Grit Fits 3/4″ Keyed Shaft 4″ Wide 4.5″ Diameter Max RPM 4000