Acer Nitro NHW820 (NP.HDS1A.008) (RETAIL) Adjustable Headband Impedance 21 Ohm Sound Pressure Level 100 dB Minimum Frequency Response 20 Hz Maximum Frequency Response 20 kHz Host Interface Mini-phone (3.5mm) Colour Black Form Factor Circumaural Weight (Approximate) 256 g Microphone Controls Noise Cancellation Microphone Technology Omni-directional Microphone Design Boom Earpiece Design Over-the-head Earpiece Type Binaural Driver Size 5 cm