Sony MDR-ZX100 ZX Series Headphones - Black (2 pack) with 2 pack Fiber Cleaning Cloth This kit includes 4 items; 2 Sony MDR-ZX100 black headphones & 2 fiber cleaning cloths High quality and powerful sound, Closed-Back Design, Thick On-Ear Cushions Pair with your MP3 player, great for outdoors Collapsible Construction, Swivel Earcups, 1.2m cable (both-sided) Driver Unit: Closed supra-aural, Dynamic 30 mm, dome type (CCAW Voice Coil), Frequency Response: 12 - 22,000 Hz, Impedance: 24 ohms at 1 kHz, Sensitivity (db): 100 dB/mW, Power Handling Capacity: 1000 mW