75 Series 15" 4Ω Dual Voice Coil Subwoofer MTX Audio
CT SOUNDS 6.5 Inch Car Subwoofer – Dual 2 Ohm Impedance, 400W Maximum Power Capacity, 1.6” Voice Coil High Frequency Subs with Rubber Edge for Vehicle Stereo Sound System - Meso 6.5 D2 : Amazon.com.au: Electronics
Dual Voice Coil (DVC) Wiring Tutorial – JL Audio Help Center - Search Articles
JBL Control SB-2 10" 8 ohm Stereo Input Dual Coil Subwoofer | AV Australia Online