1. ACTIVE NOISE CANCELLING: Internal precision noise reduction circuitry effectively eliminates up to 85% of background noise,Ideal for use when traveling by airplane,making it a must-have for peaceful sleep and enjoyable audio experience in airplane.or simply when encountering noisy environments in daily life. 2. PREMIUM HIFI SOUND -Premium 40mm diameter stereo driver units ensure a high quality auditory experiencefeaturing rich bass, as well as powerful and balanced sound.EINFACHER ENTWURF?aDie faltbare Stirnband um Platz auf dem Schreibtisch zu sparen 3. SUPER COMFORTABLE: Adjustable headband, skin texture memory foaming ear pads, lightweight around-ear fit for different head sizes, you can wear all day long. Tips: please take off the headphone in every 2 hours to get your ears relax and to get a better hearing enjoyment. 4. LONG BATTERY LIFE ��C Rechargeable Long-lasting Li-Ion Battery provides up to 15 hours of continuous use. 5. DUAL USAGE STATES ��C Never worry about being out of battery power! ��C the headphones can operate without battery power (with noise cancelling turned off).