Visonik V123BP Bandpass enclosure with dual 12" subwoofers at Crutchfield
Amazon.com: Dual Electronics BP1204 High Performance 12 inch Car Audio Subwoofers in a Tuned Bandpass Enclosure with Blue illumiNITE LED Illumination and Plexiglass Viewing Windows and 1,100 Watts of Peak Power : Electronics
Bandpass Enclosure Characteristics – JL Audio Help Center - Search Articles