Application Summary: 2003-2006 GMC Sierra 1500 Base SL SLT WT SLE (Bed Length: 78.0 & Bed Type: Fleetside & Doors: 4 & Body: Extended Cab Pickup); 2007-2007 GMC Sierra 1500 Classic SL SLT WT SLE (Bed Length: 78.0 & Bed Type: Fleetside & Doors: 4 & Body: Extended Cab Pickup); 2003-2004 GMC Sierra 2500 Base SLT WT SLE (Bed Length: 78.0 & Bed Type: Fleetside & Doors: 4 & Body: Extended Cab Pickup); 2003-2006 GMC Sierra 2500 HD Base SL SLT WT SLE (Bed Length: 78.0 & Bed Type: Fleetside & Doors: 4 & Body: Extended Cab Pickup); 2007-2007 GMC Sierra 2500 HD Classic SL SLT WT SLE (Bed Length: 78.0 & Bed Type: Fleetside & Doors: 4 & Body: Extended Cab Pickup)