HP002U model 40mm speaker 116 dB is the sensitivity. Impedance: frequency of 32+-15 Reaction: 20–20 kHz Omnidirectional microphone Mic Drive unit: 6.0 x 5 mm Mic Sensitivity: 35+-3 dB Interface: 3.5 mm Jack's measurements are 170*70*180 mm. Length of Cable: 1.80 mm