Product description 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 ENTWURFDie 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 Rechargeable Long-lasting Li-Ion Battery provides up to 15 hours of continuous use. 5. DUAL USAGE STATES Never worry about being out of battery power the headphones can operate without battery power (with noise cancelling turned off).