Visaton FRWS 5 R. Driver size: 50.8 mm (2 "). RMS rated power: 4 W, Peak Music Power Output (PMPO): 10 W, Frequency range: 150 – 20000 Hz. Diameter: 50 mm, Weight: 98 g. Type: In-wall/On-wall/In-ceiling speakers, Dimensions (WxDxH): 50 x 50 x 24.5 mm, Audio output channels: 1.0