Subwoofer High Volume Wireless Audio Bluetooth $ 11.87 Product information: Function: Waterproof, dustproof, anti-drop, call function Type: Bluetooth speaker Connection method: Bluetooth connection Interface type: USB Battery capacity: 500mAh Frequency response range: 40Hz-20KHz Power supply mode: built-in lithium battery Channel: 2 Playing time: 8 hours Bluetooth protocol: 4.1 Number of speakers: 2 Effective distance: 10 meters Operation mode: button Play format: MP3, WMA, WAV Shell material: metal Speaker adjustment method: button Box material: metal Appearance size: Mini Product weight: 0.195 (KG) Packing list : Bluetooth speaker X1