Visaton FR 10 HM. Driver size: 101.6 mm (4 "). RMS rated power: 20 W, Peak Music Power Output (PMPO): 30 W, Frequency range: 95 – 22000 Hz. Transducer material: Paper. Diameter: 100 mm, Weight: 0.34 kg. Operating temperature range (T-T): -25 - 70 °C