AKG HSD 171 professional headset, closed back, supraaural dynamic headphones, frequency range 18-26.000 Hz, sensitivity 94 dB, rated impedance 55 Ohm, Rated impedancet, microphone: dynamic, hypercardioid, frequency range 60 - 17.000 Hz, weight 255g, colour matte black, flexible microphone arm with shock mounted transducer, attention: cable is not included, please order optional !