5.1-channel amplifier Real 5.1-channel input/output, 1 AUX input Highly magnetically shielded All-function remote control Plastic towers speaker Tower speaker: Drive unit: Front: 3 inches x 4 + tweeter Surround and center: 3 inches x 2 + tweeter Frequency: 250Hz-20kHz Sensitivity: 87dB Impedance: 8 ohms Power: 30W Subwoofer: Drive unit: 8 inches Frequency: 38Hz-250Hz Sensitivity: 87dB Impedance: 8 ohms Power: 60W THD< 1% decoder or FM radio (optional) 2.4GHz wireless surround speaker (optional)