Features: 1) With MIC switch used for stereo earphone to enjoy great music 2) External design: different colors available 3) With volume control available 4) High sensitive condenser electric microphone 5) Compatible with various kinds of mobile phones Specifications: 1) Frequency response: 20Hz - 20kHz 2) Impedance: 32 ohms 3) Sensitivity: 105&olusmn;5dB 4) Max. input power: 10mW Inner packing: Polybag or customized Outer packing: Carton