Product Name: Fineblue FA-90 Bluetooth version: V4.1 and compatible with V3.0, V2.0 Size: 35 * 25 * 26 mm Transmission frequency: 2.4GHz Charging voltage: DC 5V Charging current: 80mA Talk time: about 5 hours Song time: about 4.5 hours Standby time: about 80 hours System Voice: Chinese / English (default English) Sports Bluetooth Headset Binaural Stereo Connect two phones at the same time. Voice prompts: call the newspaper, reported power free to switch between Chinese and English Color: black, white, rose gold Product Name: Fineblue FA-90 Bluetooth version: V4.1 and compatible with V3.0, V2.0 Size: 35 * 25 * 26 mm Transmission frequency: 2.4GHz Charging voltage: DC 5V Charging current: 80mA Talk time: about 5 hours Song time: about 4.5 hours Standby time: about 80 hours System Voice: Chinese / English (default English) Sports Bluetooth Headset Binaural Stereo Connect two phones at the same time. Voice prompts: call the newspaper, reported power free to switch between Chinese and English Color: black, white, rose gold