Compliant with Bluetooth V1.1 . V1.2 Specification Adopting CSR Blue Core 02 series chipset Support Bluetooth Headset and Hands free profiles Comfortable wearing Smart & nice appearance Low radiation Internal Lithium Polymer Battery Long standby time High quality of voice communication Incoming call redial Mute function Simply operating LED indicator and tone alert for headset status Frequency range: 2.4GHz~2.4835GHz unlicensed ISM band Output Power: less than 4dBm (class 2) Effective Distance: Up to 10m (30 feet) outdoor Security: Pairing, encryption, authentication BH209 Stand- By Time: 150 Hours Talk Time: 3Hours Battery: Li-Polymer battery 120mAh