Amazon.com: Rockville RVW1800P4 1800w Raw DJ Subwoofer 4 Ohm Sub Woofer 107OZ Magnet, 18" : Electronics
CocinaCo 40mm 4Ohm 5W Full Range Audio Speaker Bass Loudspeaker: Amazon.com: Tools & Home Improvement
Amazon.com: Massive Audio MB8 MB Series. 8 Inch 400 Watts, 4 Ohm Pro Audio Midrange/Midbass Speaker for Cars, Stage and DJ Applications. Sold Individually. : Electronics
Amazon.com: Fielect 2Pcs DIY Magnetic Speaker 3W 4 Ohm Full Range Audio Speaker Stereo Woofer Loudspeaker Replacement for Arduino, 52mm Diameter : Electronics
Amazon.com: BOSS Audio Systems CH10DVC 1500 Watt, 10 Inch, Dual 4 Ohm Voice Coil Car Subwoofer : Everything Else
Amazon.com: SAVARD Speakers HiQ Series 6.5" inch Dual 4 Ohm Subwoofer : Electronics
Amazon.com: Skar Audio EVL-15 D4 15" 2500 Watt Max Power Dual 4 Ohm Car Subwoofer : Electronics
Amazon.com: Gikfun 2" 4Ohm 3W Full Range Audio Speaker Stereo Woofer Loudspeaker for Arduino (Pack of 2pcs) EK1725 : Electronics
Amazon.com: PRV AUDIO 4 Inch Midrange Speaker 4MR60-4, 60 Watts Program Power, 4 Ohm, 30 Watts RMS Power Pro Audio Loudspeaker (Single) : Electronics
Amazon.com: Granvela 20W 3-inch All Frequency Range 4-Ohm Speakers Pair of Flax-Fiber Cone for DIY Multi-Media Speakers | Computer Speakers : Electronics