the box PA 18 ECO MKII, Passive 18"" Subwoofer with Built-In Crossover, Power rating: 425 W RMS / 1700 W peak, Impedance: 8 Ohm, Sensitivity: 100 dB (1 W / 1 m / 80 Hz), Frequency range: 40 - 250 Hz (-3 dB), Input and output: Speaker Twist, Top out with low cut, M20 stand mount, Dimensions: 600 x 650 x 650 mm, Weight: 41 kg, Suitable cover: Article no. #399625# (not included)