Bluetooth Version: Bluetooth V2.1 + EDR Transmission distance: ? 10M USB charging power: DC 5V, current less than 500mA Built-in battery: lithium battery 500mAh Output power: 5W Frequency response: 90Hz-20KHz Sensitivity: 80db ± 2db Signal to noise ratio: ?73dB Product size specifications: 85.3 * 74 * 74.5mm