The JTS HP-20 headphone features high quality semi closed-ear, dynamic stereo powered by a beefy yet lightweight neodymium-ferrous rare earth magnet system with lightweight copper-clad aluminum voice coils. The adjustable frame allows for a comfortable fit and hours of wear without fatigue. The coiled cord is gold-plated mini stereo phone plug, and a 1/4" phone adaptor Super thin 40mm diaphragm drivers powered by the neodymium magnet a full range 20-20,000 Hz frequency response, letting you hear all the highs and lows!