Detailed Product Description Stereo earphone1) Mic Type: 6mm x 5mm2) Impedance:maximum2.2KΩ3) Sensitivity: -58db ± 2db(0db=1v/pa)4) S/N Ratio:More than 60db5) Sensitivity Reduction:Within-3db at 1.5v6) Mic Frequency Range:30Hz-16,000Hz7) Speaker: 15mm8) Sensitivity:98db S.P.L at 1kHz9)Plug Type: 3.5mm