infobit iSpeaker M400

USB + Bluetooth + Dongle connection
360° Omnidirectional Speakerphone with 5 meters pickup range
Built-in 4,000mAh battery with 18 hours talking time
Small and portable size
Echo cancellation
Buttons: Bluetooth, Mic mute, Volume +, Volume -, Pickup/ hang up, power
Cascading: daisy chain 2 sets M400 speakerphones by 3.5mm Audio cable