CS1214 | 30 cm (12 inch) subwoofer, with double magnet suitable for enclosed, bass reflex and bandpass boxes
Amazon.com: 15" Subwoofer 1000W Single 4 Ohm Bass Pro Car Audio American Bass DX-15 : Electronics
JBL CS1214 1000-watt, 12" Car Audio Subwoofer, Black - Walmart.com
Amazon.com: Pyle 10" Car Audio Speaker Subwoofer - 1000 Watt High Power Bass Surround Sound Stereo Subwoofer Speaker System - Non Press Paper Cone, 90 dB, 4 Ohm, 50 oz Magnet, 2