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Alpine SWX-1043D Type-X 10" subwoofer with dual 4-ohm voice coils at Crutchfield
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Dayton Audio MX10-22 10" Max-X High Excursion DVC Subwoofer 2 Ohms Per Coil
Sundown Audio Xv3 18" inch DVC Dual 2 Ohm (X Series) Car Subwoofer 2000 Watts RMS
For-x X8-D2 subwoofer da 20cm 2 bobine da 2 ohm 500 watt rms 1500 max – Audioevolutionhifi
Amazon.com: BOSS Audio Systems CXX10 Chaos Exxtreme Series 10 Inch Car Subwoofer - 800 Watts Max, Single 4 Ohm Voice Coil, Hook Up to Amp : Electronics
Custom Ported Sub Box Enclosure for 1 12" Sundown X-12 Subwoofer - 32 Hz 2.6 CF | eBay
Audio System X15-1100 12" 550 Watt Dual-4-Ohm Kevlar Car Audio Subwoof - Showtime Electronics