Focal SB 30A1 Access Line 12" Sub with Enclosure Product features Load: Vented Max. power: 500W Nom. power: 250W Sensitivity (2.83V/1m): 94dB Frequency response (+/-3dB): 40Hz - 500Hz Nominal impedance: 4 Ohms Subwoofer: 30cm (12") all weather woven glass fiber cone Magnet: 145mm (5.7") Voice coil: 50mm (2") Dimensions: 360 x 390 x 527mm (14.2" x 15.4" x 20.75")