Sony MDR-ZX300AP/B Premium Lightweight Stereo Headphones with In-line Microphone and Configurable Remote for Android Smartphone (Black) Driver Unit - 30 mm Frequency Response - 10 - 24,000 Hz Impedance - 24 ohms at 1kHz Sensitivity (db) - 102 dB/mW Magnet - High-energy Neodymium