hi fi headphone Item Number: BZ-830 Newest and fashionable design, overall design in line with somatology; Small and exquisite design for wearing comfort SPECIFICATIONS Loudhailer diameter: 40mm Frequency range: 20~ 20000Hz Sensitivity: 110dB Impedance: 32 Ohm Cable length: Approx.1.5m( Volume Control) Maximum power input: 100mW pulg( mm) : 3.5 Stereo