Muc off claw brush muc off claw brush is designed to clean your rear cassette drivetrain and derailleur whilst caring for your bikes delicate finish muc off claw brush features tough impact resistant handles with ultra stiff nylon bristles combination handlecomb allows for easy cleaning of tough grime around rear cassette includes hanger on handle for easy storage 9 speed compatible buy muc off claw brush from chain reaction cycles the worlds largest online bike store