Sennheiser HD600 Open Back Professional Headphone - Black, NOB ————- Contents: Come with full accessories in retail box. New Opened Box Condition. ————- Open circumaural high-definition stereo headphone High-quality open metal mesh earpiece covers aid in delivering extremely transparent sound Computer optimized magnet system minimizes harmonic and intermodulation distortion Duofol diaphragms to reduce standing waves for distortion free sound Neodymium ferrous magnet system ensures optimum sensitivity and dynamic response Extremely lightweig