Function: speaker/handsfree/TF card/FM radio Material: metal Logo: silkscreen/laser carving Packing: blue gift box with window/white gift box optional Bluetooth version: JR3.0. Frequency: 2.402-2.480GHz. Mxx power output: 3W  Mic sensitivity: -32dbB Receive sensitivity: better than +82dBm. Range: 10 meters  Data transmission: up to 3Mbps UART data transmission rate: 115200bps . Charging voltage: 4.8V –5.2V DC. Working voltage: 3.7V –4.2V DC. Working current:  300MA. Quiescent current: >1UA. Battery: 400mAh. Antenna: built-in