Noise Cancelling reduces up to 95% ambient noise Swivel， folding design for ultra-portability 30mm dynamic driver unit for clear and rich sound 80 hours battery life (Noise Cancelling on) Works even when battery is depleted (passive operation) Type Closed Driver Unit 30mm Dynamic Frequency Response 10Hz-22，000Hz Sensitivity Power ON 115 dB/mW， OFF 110 dB/mW Impedance (at 1 kHz) Power ON 220 Ω， OFF 45 Ω Cable 1.2m Y-Type Plug L-shaped Gold-plated Stereo Mini Approx. Weight(excl. cable) 150g incl. battery Active Headphones Headphone Power Indicator LED (green) Batteries Dry Battery(Size AAA) (batteries not included) Battery Life Max. 80 hours (alkaline battery)， 40 hours (manganese battery)