Neodymium magnets and Duofol diaphragms for excellent sound reproduction : High-quality Bluetooth 2.1 wireless transmission - Optimised performance when paired with a Sennheiser Bluetooth adapter : Supports Audio Processing Technology apt-X - Sophisticated audio compression technique for true hi-fi quality : Collapsible, metal-reinforced headband ensures portability and durability : SRS surround sound mode for a more immersive listening experience : Integrated track and volume controls for enhanced usability and convenience : Single-sided audio cable included : Extensive accessories included - multi-country charger, rechargeable lithium polymer battery and carrying pouch : Optimized for MP3, CD and DVD players, iPod, iPhone and mobile phones (3.5mm stereo plug) : Bluetooth version 2.1 + EDR : Supported Profiles A2DP, AVRCP : Codec APT-X, SBC : Operating time 10 hours per full charge : Range = 10m or about 30 feet : Transducer principle Dynamic, closed : Ear coupling Circumaural : Frequency response (headphones) 15 - 22000 Hz : Impedance 590/100 ohms (Active/Passive) : THD total harmonic distortion < 0.1% (1kHz) : Sound pressure level (SPL) 107 dB (1 kHz / 1 Vrms) : Battery Specification 3.7 V rechargable lithium polymer : Cable length 1.4 m : Weight 179 g : Sennheiser 2 year warranty : Delivery Includes - 1 PX 360 BT / 1 single-sided audio cable / 1 inflight adaptor (3.5 mm double mono jack) / 1 6.3 mm audio adaptor / 1 USB charging cable / 1 rechargeable lithium polymer battery / 1 carrying case