HG8902 Specifications Sound: stereo Frequency response: 20 Hz - 20 KHz Speaker size: 50 mm Speaker impedance: 21 Ω Speaker sensitivity: 119 dB ± 3 dB Microphone type: omnidirectional Microphone size: 6x2.7 mm Microphone sensitivity: -38 dB ± 3 dB Backlight: rainbow Connectors: USB Cable length: 2.1 m Feature Closed, over-ear design for powerful bass sounds Soft-cushioned leather ear cups Self-adjustable headband Built-in volume control Solid, reinforced structural housing