QPower QBOMB8V Dual 8 Inch Vented Port Subwoofer Sub Box with Bedliner Spray

Dual vented chamber design Middle slot port Durable black bed liner spray finish Spring loaded terminals Size: 8-inch MDF construction: 0.75-inch Air space (per sub): 1 cubic feet Tuning frequency: 40 hZ Dimensions: 28 x 13 x 13 inches Cutout diameter: 7.25 inches