Protable MP3 Earphone

Model: ITUBE 3C
Driver: Wideband MicroDrivers, Balance Armature
Sound Pressure Sensitivity: 115dB+/- 3dB 1mW 1KHz
Frequency Response: 10 ~ 20KHz
Impedance: 30 OHM +/- 15% (DC)
Rate input: 2mW
Max input: 20mW