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Amazon.com: Audiopipe 6" Woofer 150W Max 4 Ohm DVC Sold Each : Electronics
Amazon.com: Fielect 2Pcs DIY Magnetic Speaker 3W 4 Ohm Full Range Audio Speaker Stereo Woofer Loudspeaker Replacement for Arduino, 52mm Diameter : Electronics
DS18 SLC12S Car Subwoofer Audio Speaker - 12" in. Paper Glass Fiber Cone, Black Steel Basket, Single Voice Coil 4 Ohm Impedance, 500W MAX Power and Foam Surround for Vehicle Stereo Sound System
Amazon.com: Dayton Audio DAEX30HESF-4 High Efficiency Steered Flux Exciter with Shielding 30mm 40W 4 Ohm : Electronics
Amazon.com: CT Sounds STRATO-10-D4 2500 Watts Max 10 Inch Car Subwoofer Dual 4 Ohm : Everything Else
Amazon.com: Sound Town 15" 450W Raw Woofer Speaker with 4" Voice Coil, 100 oz Magnet, Replacement Woofer for PA/DJ Subwoofer, 4-ohm (STLF-1504-4) : Everything Else
Amazon.com: 1.5” Audio Car Tweeter Speaker - Aluminum Die-Cast Frame, 500 Watt Peak, 2 kHz - 25 kHz Frequency Response, 4 Ohm, Heavy Duty 30 oz. Magnet Structure - Pyle PDBT31 SILVER : Electronics
Amazon.com: Rockford Fosgate R2D4-10 Prime 4-Ohm DVC 10” Subwoofer 250 Watts RMS / 500 Watts Max : Electronics
CT Sounds MESO-8-D4 1600 Watts Max 8 Inch Car Subwoofer Dual 4 Ohm