Experience the high-quality sound your subwoofers deserve with the QPower QBomb 8 in. Quad Ported Subwoofer Box. This casing was ideally designed to fit GMC and Chevy Crew Cab from 2007 to current. The enclosure features 4 8 in. ported openings for an ideal fit. The cover is designed for the utmost durability, so you can enjoy musical longevity. Constructed from a strong bed liner material, this enclosure will protect your subwoofers from any unnecessary wear or tear. Once fitted, the enclosure will elevate your speakers to a whole another level. With underseat frontfire capabilities, the enclosure will help produce a louder and crisper sound than ever before. Feel free to turn up the bass as loud as you want, as the enclosure's design is the ideal spot for bass bumping at a comfortable tuning frequency of 35 hertz. Crank up that volume and enjoy that sound, with this QPower 8 in. Quad Ported Subwoofer Enclosure Box.