Pyle 12' Car Audio Speaker Subwoofer - 1600 Watt High Power Bass Surround Sound Stereo Subwoofer Speaker System - Non Press Paper Cone, 90 dB, 40 Ohm, 60 oz Magnet, 2 Inch 4 Layer Voice Coil -PLPW12D
Amazon.com: JBL Club 1024 - 10” Subwoofer w/SSI (Selectable Smart Impedance) switch from 2 to 4 ohm, Black : Electronics