KENWOOD P-W3041S Performance Series 12-Inch 2,000-Watt-Max Preloaded Subwoofer with Vented Enclosure - Walmart.com
JBL Stage 1220b - Dual 12" Stage subwoofers mounted in a slot-ported enclosure - Preloaded car subwoofer boxes - Custom Sounds & Tint
Amazon.com: Kenwood X502-1 eXcelon 500-Watt @ 2 Ohms Class D Subwoofer Amplifier | Plus P-XW1241S eXcelon 12" Preloaded Subwoofer Enclosure : Electronics
Alpine Jeep Wrangler Single 12-Inch Alpine Halo R-Series Preloaded Subwoofer Enclosure with ProLink R2-SB12V (Universal; Some Adaptation May Be Required) - Free Shipping