Earthquake Sound SWS-10X Shallow Woofer System 10-inch Car Subwoofer, 4-Ohm (Single)Earthquake Sound Corporation is the original inventor of the Shallow Woofer System (SWS) that produces a lot of bass from a small space Low profile and inverted style cone designs allows the SWS to have maximum excursion in shallow mount application. Protected by 3 U. S. patents, these low profile subs can be placed almost anywhere 10 inches High perfomance shallow sub; Power handling: 200 Watts RMS (400 Watts MAX) 4 Ohm; High temperature voice coil