AKG K-99 Perception Dynamic Stereo Headphones - semi-open back design, circumaural, 32 Ohms rated impedance, 220mW maximum input power, frequency response: 18Hz-22kHz, 112dB/V sensitivity, single sided jack connector, includes gold-plated 1/8" to 1/4" adapter. Cable length: 3m (with 3.5mm stereo mini-jack). Weight: 210g (without cable)