4 Ohm 8 Inch Subwoofer Speaker | Inches 4 Ohm Speaker Woofer - 1pcs 4 Inch Audio - Aliexpress
30 inch sub - ecoustics.com
15 inch Subwoofer Replacement PRO DJ Speaker Sub Woofer Loudspeaker Wide Full Range Loud Aluminum Frame,2200W PMPO, 90oz Magnet, y-30 Grade Powerful Magnet 5 Core (15185 08 AL) - Walmart.com
Pioneer GXT-3730B Car subwoofer enclosure 30 cm 1400 W 4 Ω | Conrad.com
Focal Access 30 A1 12" 4-ohm subwoofer at Crutchfield
Hifonics CX12D2 30 CM (12 ") Spl Colossus Subwoofer 8000 Watt Power | eBay