Serioux Bluetooth handsfree headphones headband, can be used as audio headphones or as a handsfree device, compatible with most mobile devices, Bluetooth V3.0+EDR technology, charging time approx. 3h, talk time approx. 6h, autonomy in headphone mode approx. 4h, standby time approx. 60h, maximum working distance 10m, maximum microphone working distance 1m, color black