Brand Rapoo Model H8030 Wireless Type 2.4G Color Deep Pink Interface Type Wireless USB receiver Distance 10 M Impedance 2.2 ohm Sensitivity -46 dB Headphone Frequency Response 20~20000 Hz Working Voltage 3.7 V Sound Card Yes Features Built-in 450mAh lithium battery Charging time: 2 hours; Working time: 8 hours; OS System: Windows XP / Vista / Win7 Mac OS X 10.4 or above versions; 2.4G wireless transmission technology super anti-jamming capability in as far as 10 meters range to provide high-quality audio transmission; Adopts COM-Ti membrane technology; Rotating the microphone down to the communication position and up to the mute condition Warranty 12 Months excluding physical damages (see specifications for terms and details) Packing List 1 x Wireless headphones 1 x USB receiver 1 x USB charging cable (95cm) 1 x Chinese / English / Korean user manual