Amazon.com: MB Quart DS1-204 Discus Shallow Mount Subwoofer (Black) – 8 Inch Subwoofer, 400 Watt, Car Audio, 2 Inch Voice Coils, UV Rubber Surround, Best in Sealed Enclosures : Electronics
JBL Stadium 82SSI Stadium Series 8" component subwoofer with switchable 2- or 4-ohm impedance at Crutchfield
S-84D 8" Subwoofer
Alphasonik AS8DF 8 inch 600 Watts 4-Ohm Down Fire Shallow Mount Flat E | Alphasonik
Amazon.com: CT Sounds MESO-8-D4 1600 Watts Max 8 Inch Car Subwoofer Dual 4 Ohm
Polk Audio db840DVC db Series 8" subwoofer with dual 4-ohm voice coils at Crutchfield
3XL-810D 8" Subwoofer
JL Audio 8W3v3-4 W3v3 Series 8" 4-ohm subwoofer at Crutchfield