Elac BS 243. Tweeter size: 45 mm, Woofer size: 150 mm. RMS rated power: 150 W, Peak Music Power Output (PMPO): 80 W, Sensitivity: 87 dB. Weight: 5.2 kg. Type: Bookshelf, Dimensions (WxDxH): 285 x 170 x 232 mm, Satellite speaker impedance: 4 Ом