R/T Dual 10-Inch Chevy 1500 Extended Cab 2008 - 2011 Sealed Speaker Box 49.5" width x 12.25" deep x 7" tall (DOES NOT FIT HD MODELS) Holds dual 10" sub woofers (Downfire) - Speaker mounting depth 5 3/4" Solid 5/8" material with "Tri-lock" joint construction Sealed Enclosure Designed for: Chevy/GMC 1500 Siverado/Sierra Extended Cab 2007(new body style) - 2013