8 in. high-efficiency woofer True Wireless Stereo (TWS) allows user to connect 2 speakers via Bluetooth(R) Built-in Bluetooth(R) receiver USB/micro SD(TM) and auxiliary inputs FM radio Rechargeable lithium battery Volume control Microphone input Built-in handle Frequency response: 90 Hz to 20 KHz Sensitivity: 90+/-2dB Impedance: 4 ohms Peak power capacity: 1,000 watts Power output: 15 watts Power input: 5-volts Includes microphone, remote, and user manual Black