Philips CSS2113, 2.0 channels, 60 W, 4 Ω, 1.5", 5", Passive subwoofer Philips CSS2113. Audio output channels: 2.0 channels, RMS rated power: 60 W. Impedance: 4 Ω, Tweeter diameter (imperial): 1.5", Woofer diameter (imperial): 5". Subwoofer type: Passive subwoofer, Subwoofer frequency range: 20 - 150 Hz, Subwoofer impedance: 8 Ω. Product color: Gray. Connectivity technology: Wireless