Philips P9BLK. System type: 2.0 system, Recommended usage: universal, Speaker placement: Tabletop/bookshelf. RMS rated power: 20 W. Connectivity technology: Wireless, Wireless technology: Bluetooth, Headphone connectivity: 3.5 mm. Width: 287 mm, Depth: 63 mm, Height (with stand): 127 mm. AC input voltage: 240 V, AC input frequency: 50 - 60 Hz, Battery technology: Lithium-Ion (Li-Ion)