Divoom voombox-travel is an ultra-portable, rugged wireless Bluetooth speaker with microphone. Rugged, splash resistant design makes it a great choice for outdoors. Latest 4.0 Bluetooth technology lets you wirelessly stream audio from tablets, smart phones, and other Bluetooth-enabled devices. Dimensions: 45R x 45H mm . Driver size: 2"full rang x 2"passive radiator . Output power: 4W . Signal to noise ratio: 75DB. Battery capacity: 550 mAh . Battery voltage: 3.7 V . Battery charge time: 2-2.5H hours. Wireless range: up to 10 meters . Bluetooth compliant: Bluetooth V4.0. Bluetooth profile support: A2DP stereo. Talk time: up to 6 hours . Microphone sensitivity: -40 DB.