ZAGG Premium Wood Headphones - Bamboo All wood ear cup housing delivers natural audio reproduction. Detachable cords for storage and transport Speaker size: 50mm / Frequency response: 20Hz  20KHz / Sensitivity: 113+/-3dB At 1KHz1mW Impedance: 40 Ohm / R&L balance&lt; 3dB(20Hz-10KHz 1mW) / Rated input power: 30mW Maximum input power: 50mW / Cable: length 1.2m TPE Material / Plug: 3.5mm gold-plate