Maxxsonics USA, Inc. OWC304 Onyx Vehicle Subwoofer Durable thermal formed polypropylene cone. Deep drawn heavy gauge stamped steel basket. Heavy duty textured powder coat finish. Rubber surround with a single spider design. These two suspension elements combine to provide MB Quart subwoofers with incredible control under any load, small or large. 12" DVC 4 ohm subwoofer 300 watts RMS 600 watts MAXX