High power 40w bluetooth speaker waterproof portable column super bass stereo for comuter pc speakers with fm radio bt aux tf specification bluetooth version: v4.2 battery capacity: 3600mah (built in) endurance time: 8-10 hours charging time: 1--2 hours speaker: 20w * 2 input sensitivity: 400mv wireless transmission distance: 10 meters the degree of separation: ¡ý90db frequency response: 70~20khz ( -3db) signal-to-noise ratio: ¡ý 80db playback formats: wav, mp3, wma, flac, ape tf maximum support: 32g(not included) mode of operation: press key usb line length: 50cm input voltage: dc 5v 2a interface type: micro usb / aux / tf card socket / 2.0 usb size: length 21.5cm, width 9.7cm, height 9.4cm