Unit: 1 Knowles Balanced Armature drivers + 4 EPZ custom composite Balanced Armature drivers Plug Type: 0.78mm double needle/MMCX Plug iameter: 3.5mm Frequency range: 20Hz-20000Hz Sensitivity: 110dB(±0.05dB) Impedance:20Ω Wire: Eight-core high-purity single crystal copper Technical Features: 3 Frequency division,3 Sound hole Craf: 3D printing