Noise Isolating Dependable Durable Studio Headphones - Black New Design for Compact Travel Dependable: Thick isolating padding helps reduce outside noises Versatile: 3.5 mm jack fits all standard audio devices, code is made from durable fabric material Maximum Power: 100 mw / Standard Operating Voltage: 4.5 V / Wire Length: About 1.2 meters Speaker Size: 40 mm / Frequency Range: 20-20,000 Hz / Speaker Impedance: 32 Ohm+/-15% / Speaker Sensitivity: 105 dB+/-3dB