Model BH-M10b (SIG: https://www.bluetooth.org/tpg/EPL_Detail.cfm?ProductID=15385 ) Quantity 1 Color Black + Silver Bluetooth Version v2.1 Ear Coupling Over the ear Talk Time 20 Hour Standby Time 350 Hour Operating Range 10 meter Compatibility Bluetooth v2.0 & 2.1 Microphone Yes Radio N/A Power Supply Built-in battery Built-in Battery Capacity 250mAh Compatible With All Bluetooth wireless technology enabled phones. Other Features Clear and high quality voice for both talking party. Voice-dialing re-dialing refusal of incoming call function. Volume adjustable. Packing List 1 x Bluetooth headphone 1 x 2-Flat-Pin plug power adapter (100~240V) 1 x USB charging cable (103cm) 1 x English user manual