Atrend A164-10 Dual 10" Subwoofer Enclosure for 2003-2007 Chevy Silverado and GMC Sierra Crew Cab Trucks Dual 10" Down Firing Subwoofer Enclosure Designed Specifically For 2003-2007 Chevy Silverado and GMC Sierra Crew Cab Trucks Coated Tough Guard Finish Glued & Braced 3/4" MDF Construction Rounded Edges