Sweex 2.0 Speaker Set Purephonic 20 Watt Red USB. RMS rated power: 2 W, Peak Music Power Output (PMPO): 20, 6 W, Frequency range: 100 - 18000 Hz. Connectivity technology: Wired. Compatible operating systems: Microsoft Windows XP, Windows Vista, Windows 7, Apple Mac OSX. Speaker power: 2 W, Dimensions (WxDxH): 65 x 70 x 176 mm, Audio output channels: 2.0