2014 and Up Chevy Double Cab Ported Subwoofer Box Sub Box 2X12 CarpetedArmor Coated With High Pressure Polyurethane Bed Liner Material Increases The Base up to four times stiffens the wood and no air leaks 100% Made In The U. S. A Fits 20144 and up Chevy Double Cab . Under the rear seat . Ported system Port volume . 029 Cu. Ft 3. 5''x2. 5''x5. 75'' 1 1 2'' clearance between the box and the truck floor . 2 8'' Woofers Material 5 8'' M. D. F Air Volume 1. 12 Cubic Feet Total Mounting Depth 5. 5'' Magnet diameter not more