1) stereo and stable sound; 2) sample available; 3) on-time delivery. 1,Plug Model : USB2,Speaker/Vibration diameter : 40/30mm 3,Speaker/ibration Impedance :32/8Ω 4,Speaker Frequency response: 20Hz - 20KHz 5,Speaker Sensitivity: 110dB 6,Noise Level :≤-78dBA7,Dynamic range: ≥78 dBA8,THD :≤0.1%9,Stereo crosstalk :≤-52 dBA10,phone Specification 6*5mm 11,phone Sensitivity : -58dB 12,phone Directivity ...