The ASB7118 High Power 18" Subwoofer is a high power, lightweight front-loaded vented subwoofer enclosure housing JBLs exclusive 2269H Ultra Long Excursion 18" Differential Drive woofer. This woofer features neodymium magnet, dual voice coils and dual gaps, JBLs exclusive Vented Gap Cooling and ultra robust composite cone for high excursion and extra long life. The woofer is capable of a peak-to-peak maximum excursion of 3.5".