The Phiaton PS 300 NC headphones are masterfully made and matched to exacting standards. With powerful noise cancelling technology that minimizes distortion while allowing authentic production values to come through, the PS300 NC allows you to listen to your music with up to a 90% reduction of most unwanted noise in your surroundings. This unit has a comfortable, compact on-ear fit with a flexible ‘fold and go’ design that fits headphones conveniently into a compact carrying case for easy travel. When on the move, the Custom lithium- polymer rechargeable battery offers up to 20 hours of reliable run time while the set of four adaptors allows you to recharge anywhere. The standard 3.5mm plug and the 6.3mm adaptor make this earphone perfect for any portable or home theater electronics. Studio Grade 40 mm Electrodynamic Drivers, Impedance: 32 Ohm, Sensitivity: 98 dB, Max input power: 1000 mW, Weight: 5 oz/140g without cord, Accessories Includes: 1 extra rechargeable lithium-polymer battery, 6.3 mm stereo gold-plated plug adapter, Dual-plug adapter for airplane, Adapter clips, Cradle charger with USB cable, Audio cable, AC/DC adapter, Carrying case, 1-year warranty.