Impedance = 4ohm Power recommendation = 20-100W Power RMS = 100W Resonance frequency = 730 Hz Frequency response = 1,4-30 kHz (Recommended 3 – 30 kHz) SPL 1W/1 Meter = 91dB Outer Diameter = 58 mm Mounting Diameter = 52 mm Mounting Depth = 36 mm.