Amazon.com: Sound Town 18” 450W Raw Woofer Speaker with 4" Voice Coil, 100 oz Magnet, Replacement Woofer for PA/DJ Subwoofer, 4-ohm (STLF-1804-4) : Musical Instruments
DS18 ZXI6.4D High Excursion 6.5" Car Audio Subwoofer 600W Watts DVC 4-Ohm Quad Stacked Magnets