Rockford Fosgate Prime R2-2X10 Sealed enclosure with two 10" Prime R2D2 subwoofers at Crutchfield
HTD Level TWO Powered Subwoofer
Sound Ordnance™ B-24 Bandpass enclosure with two 12" subwoofers at Crutchfield
Want to know the pros and cons of dual subwoofers — Theirishcurse.com
Amazon.com: Pyle 6" Dual Subwoofer Box System - Dual Series Vented Subwoofer Enclosure - Rear Vented Design with Built-in Illuminating LED Lights, 2 x 200 Watts Max Power, Two 4” Tweeters : Electronics
Amazon.com: Two Single Pioneer TS-D10LS2 D Series 10" 2 Ohm Shallow Mount Subwoofers : Electronics