These flap wheels are mounted on a 1/4" shank. Made of aluminum oxide, resin-bonded to cloth and permanently attached to the hub. They are resilient and can be used on flat or contoured surfaces. Particularly useful in flexible shaft handpieces and other rotary tools. Excellent for blending on metal surfaces, deburring and removing flash from machined parts, and edge blending of dies, molds and channels. Cutting action is slightly finer than normally expected from identical grit sizes. Flap Wheels perform best when only slight pressure is applied.