Kenwood Excelon KFC-XW800F Shallow-mount 8" 4-ohm subwoofer at Crutchfield
Kenwood P-XW1221SHP Single 12" High Power Subwoofer in a Vented Enclosure and includes a X502-1 1000W Max Power eXcelon Series Class D Mono Amplifier - Walmart.com
Kenwood XR-W10F 10" Oversized Shallow Subwoofer, 1200W Max Power - Creative Audio
Kenwood Excelon KFC-XW1200F Shallow-mount 12" 4-ohm subwoofer at Crutchfield