Tera Bluetooth4.0 Super Mini Stereo Earphone Headphone Headset Earbud Wireless Invisible for Smartphone Hands Free Call Music khaki Ergonomic design and sweat proof for any hands free activity. Support simultaneous connection of two Bluetooth device. Easy to control the music or call by the button on the ear buds. Support voice report phone call number. Support Chinese and English freely switch. Support USB charging. Bluetooth V4.0+EDR. On call time: about 4hours. Music play time: about 3hours. Standby time: about 120hours. Dimension: approx.27x15x14mm/1.1x0.6x0.6". Suitable for mobile phone, tablet PC or any device with Bluetooth function.