The Punch 300-8P is a universal "all in one" self-contained subwoofer enclosure with built-in amplifier for dropping Bass in any factory or aftermarket system The 8" high output subwoofer is impedance optimized for the built in 300-watt class-D amplifier in a slim design enclosure - Dimensions: 11.4" x 17.6" x 5.6" Featuring an adjustable 12db/Octave low pass crossover, on board adjustable bass boost EQ, and on board phase switch The enclosure can be connected via speaker level inputs for connection to factory systems, or traditional line level inputs for aftermarket systems Famous Rockford Fosgate build quality with a full 1-year warranty The Punch 300-8P is a self-contained subwoofer enclosure with built-in amplifier. This "all in one" solution is great for systems that need extra Punch on the low-end of the frequency spectrum. The 8" high output subwoofer is impedance optimized for the built in 300-watt class-D amplifier that features a low-pass crossover, bass EQ and phase switch. The enclosure can be connected via speaker level inputs for connection to factory systems, or traditional line level inputs for aftermarket systems. It also features an intelligent auto turn-on/off circuit that eliminates the need for a separate turn-on wire. The enclosure itself is precision designed and constructed using MDF (Medium Density Fiberboard) for the best acoustical properties and covered with heat activated vinyl finish to resist marks. Dimensions: 11.4" x 17.6" x 5.6"