Qpower Shallow110 Single 10 Inch Vented Shallow Subwoofer Sub Box Enclosure : Target
15" Dual Sealed Compact Sub Box 15" Subwoofer Enclosure Ground Shaker Sub Box | eBay
MT21A Built-in DSP single 21" Self-powered Subwoofer with Compact Cabinet Box - Buy 21" subwoofer, single 21 inch subwoofer, self powered subwoofer Product on Sanway Professional Audio Equipment Co., Ltd.
Alpine SBR-S8-4, Compact R Series Loaded 8" Subwoofer Enclosure System – AVLeaderz
Underseat 10-Inch Subwoofer Enclosure for Full-Size Trucks and Other V - Phoenix Gold