Product Name: Dynamic Mini Earphone UnitModel Number: EDX0901Place of Origin: ChinaFeatures: 1) This product is super miniature designed, and clearly sound quality, bass effect and the high SPL, wide-band, function stability, and quality credibility 2) Can be used extensively for speech and music, heavy play of the music earphone, blue tooth headset, and the mobile phone 3) And the frequency can make to order according to the customers 4) Rated input: 10mW 5) Max. input: 20mW 6) Frequency range: 100 - 2,000Hz 7) Impedance at 1kHz: 32±15%Ω 8) SPL at 1kHz (179mV): 109±3dB