The Focal BUS 20 Bomba is an 8-inch active subwoofer designed to be placed under the seat of a vehicle. With a power output of 150W RMS, this non-enclosed subwoofer features a single voice coil and operates in a 2-channel system. The rectangular shape and built-in amplifier make it a compact and powerful addition to any car audio setup, providing rich and deep bass for an immersive in-car entertainment experience.