DAS Audio Altea-718, Passive 18"" Bass Reflex Subwoofer, Power rating: 600 W RMS / 2400 W peak, Frequency range: 45 - 138 Hz, Maximum output level: 134 dB, Impedance: 8 Ohm, Connections: Speaker twist, 35 mm Speaker stand flange mount, Dimensions (H x W x D): 720 x 545 x 650 mm, Weight: 40.5 kg, Colour: Black