Logitech Z520. RMS rated power: 26 W, Frequency range: 70 - 20000 Hz. Speaker interface type: 3.5 mm. Minimum system requirements: Windows XP / Windows Vista Mac OS X 10.3.9 3.5 mm. Type: TV/Monitor speakers, Audio output channels: 2.0, Surround speaker dimensions (WxHxD): 198.1 x 88.9 x 88.9 mm