The new R2-Series subwoofers now feature larger, double-stacked magnets that contribute more motor force for deeper bass and tighter bass control compared to the previous generation.ProLink is unique to Alpine and allows you to link two R2-SB12V enclosures together using an optional KTX-H12 Linking Kit (sold separately) to create a dual subwoofer-enclosure.Drawing inspiration from the sleek, tapered lines and clean silver finish of the Alpine Halo Display, the R2-SB12V shares the same unique, curved edges outlined by a silver trim and a metallic front baffle for a matching system aesthetic.The ported enclosure design features an optimized vent and rounded internal port edges that maximize the output performance of the subwoofer.Made from 3/4" medium density fiberboard (MDF) with internal edge bracing, the R2-SB12V is sturdy with a rugged, yet stylish black carpet cover and brushed aluminum finish on the metallic front baffle.The R2-SB12V includes a preloaded R2-Series R2-W12D4 12" subwoofer that's turned to 35Hz for optimized performance with Alpine's R2-Series sound system line.Dual 4Ω voice coils are wired in parallel for a 2Ω load that's compatible with the R2-Series R2-A75M Mono Power Amplifier. Key Features Groundbreaking Alpine Halo Design Vented Enclosure Tuning Frequency: 35Hz Sensitivity 85dB ProLink ported enclosure design Optimal Sound Performance 750W RMS Power Handling Includes preloaded R2-W12D4 12” R2-Series subwoofer CARB compliant 3/4-inch MDF construction Premium black carpet Silver Alpine embossed side logo badge Brushed aluminum finished metallic front baffle 17” W x 14.625” H x 15” D Dual 4Ω Voice Coils Wired in Parallel for a 2Ω Load (Compatible with R2-A75M) 12 Gauge OFC Speaker Box Wire Binding Post Terminal Cup Threaded Subwoofer Mounting Inserts (for reversible subwoofer orientation) 2Ω Impedance Frequency Response: 24-200Hz