Rated Impedance: 8Ω± 15%
Rated Power: 25 W
Max. Power: 40 W
Resonance Frequency: 330 Hz ± 20%
Whistling : 2.8 Volts  
D.C Resistance (Rdc): 6.8 Ω± 10 %
Magnet: 31*5mm (Neodymium)
Dimension: 82 ^L x 72 ^W x 37 ^D mm
Weight 140 gram