Trust 2.1 Speaker Set SP-3920, 2.1 channels, 70 W, 35 - 20000 Hz, 5.25" Trust 2.1 Speaker Set SP-3920. Audio output channels: 2.1 channels, RMS rated power: 70 W. Satellite speaker frequency range: 35 - 20000 Hz. Subwoofer driver diameter (imperial): 5.25"