The streamlined design of this headset means great wearibility.Stable neckband means versatility for use conditions. Seamless switching between music and calls. Great sound with control. Bluetooth specification 2.0 + EDR (enhanced data rate). Headset profile 1.1, hands-free profile 1.5, advanced audio distribution profile (A2DP) 1.0 and audio vedio remote control profile (AVRCP) 1.0. Working range: 10 meters (33 feet). Talking time: Up to 13 hours when battery in full condition. Music playing time: Up to 13 hours when battery in full condition (or 75 minutes of music playing time with 20 minutes charging). Standby time : Up to 240 hours. Charging time: 1.25 hours for fully charge. Frequency Response: 22-18000 Hz. Compatible with : Various Bluetooth enabled devices, such as mobile, PC, laptop, MP 3/4/5,and so on.