BESTISAN Powered Subwoofer, Deep Bass Subwoofer, Down Firing Sub in Compact Size, Easy Setup with Home Theater System, TV, Receiver, Speakers (RCA Cable Included, Black),SW65C - Yahoo Shopping
Amazon.com: Pyle 8'' Active Down Firing Subwoofer - Home Theater Surround Sound Black w/Sealed Design, Magnetic Design w/Sleek Black Color, Down Firing Port for Deeper Bass Resonance - PSUB8A : Musical Instruments
Amazon.com: KICKER TRTP 8-inch (20cm) Thin Down Firing Subwoofer and Passive Radiator Enclosure, 2-Ohm, RoHS Compliant : Electronics
Kicker 48CDF124 Comp Series 150W 12" Sealed Down Firing Subwoofer Enclosure 713034020332 | eBay
Pyle Active Down Firing Subwoofer - 10 Inches, Ported Design with High-to-Low Input Level Controller, Invisible Down-Firing Speaker, Color Black, Built-in Convenience - PSUB10A - Walmart.com
Down Firing vs. Front Firing Subwoofer - Blog - REL
Kenwood Excelon P-XRW122DB Reference Series down-firing sealed enclosure with one 12" subwoofer at Crutchfield
Kicker Comp RT 12" Down Firing Subwoofer Kit with Box: TRTP112-SK
HOW DOES IT SOUND? - Downfiring Subwoofer Build Finished! - YouTube