The PFERD mounted flap wheel features 40-grit aluminum oxide abrasive for consistent stock removal, with fresh, aggressive abrasive continually exposed throughout its service life. Its flexible design conforms to contours, while the flat molded core allows face-down use close to edges and in corners. The wheel measures 2 1/2 inches in diameter by 1/2 inch wide and has a 1/4-inch shank.