This bundle contains two Alpine SBR-S8-4 Loaded 8" ported Type-R enclosures. Loud, Clean Bass That Fits AnywhereThe SBR-S8-4 8” Enclosed Subwoofer lets you add deep, accurate bass to your sound system without taking up much space in your vehicle.Type-R TechnologyThe SBR-S8-4 uses the same 8” subwoofer available in the Type-R component subwoofer lineup, so you get high excursion combined with high power handling. This advanced Type-R motor structure converts your amplifier’s output to low bass you can feel.More bass, less spaceThe SBR-S8-4 is compact and very shallow (only 11 1/2” wide x 19 1/4” long x 5 1/2” deep) allowing it to be mounted in virtually any vehicle. This compact subwoofer system works well under or behind the seat of a pickup truck, in a sedan trunk, or in the hatch of an SUV. /p>Tuned to rockIn order to play low with minimal power input requirements, the SBR-S8-4 is ported. A low tuning frequency combined with an efficient, large cross-section port allows the system to play down to the lowest octaves while still maintaining excellent control and power handling characteristics.Killer cosmeticsHigh-quality carpeting and sleek laminate combine to give the SBR-S8-4 great looks. A strong, attractive Type-R grille protects the woofer’s cone from damage, and the flush-mount spring-loaded terminals make connecting large-gauge wire a snap.Durable constructionUnlike many low-cost enclosures, the SBR-S8-4 is constructed from the best materials. High-quality MDF is used for all structural components, and it is internally braced to add stiffness and durability.Amp it up350 watts of RMS power handling make the SBR-S8-4 compatible with a wide range of mono and multi-channel amplifiers. For example, hook it to the subwoofer channel on the 5-channel Alpine MRX-V60, or connect it to two bridged channels on an Alpine MRX-F30…either way you’ll get great low-bass performance.