IDQ8 V.4 D4 | Image Dynamics 8" Dual 4-Ohm IDQ V.4 Series Subwoofer
FEATURES:

Nominal Impedance: Dual 4-Ohm
DC Resistance: 2.9 Ohms
Resonant Frequency: 35.05 Hz
Electrical "Q": 0.64
Mechanical "Q": 1.31
Total "Q": 0.43
Equivalent Volume: 0.57 cuft (16.20 Liters)
Peak Excursion: 14mm
Piston Area: 216.42 cm2
Sensitivity w/m: 82.20 dB
Force Factor: 13.07 Tm
RMS Power: 500W
SPECIFICATIONS:

Speaker Displacement: 0.05 (1.42 liters)
Mounting Depth: 125.75mm (4.95")
Cut-out Diameter: 184.40mm (7.26")
Screw Hole Diameter: 197mm (7.76")
Outside Diameter: 212mm (8.35")