Features and Benefits:Lowers harmonic vibrations that can cause friction induced braking noise; The Flex-Hone for Rotors reduces high pitched "squeal" and "groan" caused by a peaky, rough turned finish; More rotors per hone lasts much longer than abrasive pads; Non-directional finish spiral grooves on the braking surface are a prime cause of friction induced brake noise - ideal for new rotors, too!; Removes the cut, torn and folded metal fragments from the surfaceThe Flex-Hone tool from Brush Research has set the industry standard for excellence in honing tools. Our flex hones for rotors are specially designed to provide the ideal surface finish for disc brake rotors and flywheels. With the ability to finish more rotors per hone, we know our honing-tools will be the answer to your rotor needs.