Grandstream GUV3050, HD Bluetooth Headsets with Noise Canceling Mic (GUV3050) Connection - Bluetooth 4.2, allows for dual connectivity for two Bluetooth devices simultaneously Bluetooth - Class 2 and Bluetooth 4.2 Talk time - Up to 12 hours Audio control - Hook off/on, Mic Mute, Speaker volume up/down on headset Integrated busy light - Red lights on both ear cups are activated automatically when on a call Speaker bandwidth music mode - 20Hz - 20kHz Speaker bandwidth communication mode - 150Hz - 6.8kHz Microphone type - Medium-length boom arm with Noise Canceling unidirectional Microphone frequency range - 150Hz - 6.8kHz Packaging dimensions Headset: - 155x36x180mm Charging stand: - 100x81x108mm Packaging - User Guide, GUV3050 BT headset, GUV-UDG01 Bluetooth USB adaptor, charging stand Headset Weight - 158g