The line array speaker system includes 1 x ZETHUS-218S passive line array subwoofer, 4 x ZETHUS-210B passive line array speakers, and 1 x ZETHUS-SF1 stack adapter The ZETHUS-218S is a high-power passive line array subwoofer. With two 18 woofers and one 4' voice coil built in, the ZETHUS-218S subwoofer handles 1600W RMS / 3200W peak power output, and delivers deep, rich and punchy bass The ZETHUS-210B is a lightweight and compact line array speaker. It comes with two 10 woofers and one 1.4 compression driver with 550W RMS, 1100W peak power handling capability Four ZETHUS-210B line array speakers can be quickly stacked on top of the ZETHUS-218S subwoofer and secured with the stack adapter ZETHUS-SF1. Altogether they deliver accurate and immersive sound performance at earth-shaking volume Perfect for live sound venues such as stages, bars, ballrooms, restaurants, houses of worship, convention centers, theaters and more