Thermos flask and speaker in one. Double-walled stainless steel thermos flask for keeping drinks warm or cool for a long time. With beautiful matt black finish and screw lid. The removeable bluetooth (version 4.2) speaker on the bottom is compatible with the most common smartphones and tablets. Range up to 10 meters. Ideal during your workout. Power 3W. Frequency: 20HZ-20KHz. With built-in 600mAh li-ion battery for hours of listening pleasure. Bottle contents 350 ml. Includes micro-USB charging cable and user manual. Each item is individually boxed.