Cutouts on each side allow the mattress to fit around and over the wheel wells in the truck bed, allowing for a more complete sleep area, This utilizes the entire truck bed, providing more room and comfort to the outdoor enthusiast, **Please note: Short bed sizes are for 6" to 6, 5" beds and not 5, 5" to 5, 8" beds, AirBedz can only be used in 5, 5" to 5, 8" beds with the tailgate down, **, Fits the following size trucks:, 1973-2010 - Chevrolet Silverado 6" 6"" Short Bed, 1973-2010 - GMC Sierra 6" 6"" Short Bed, 1994-2010 - Dodge Ram 6" 4"" - 6" 6"" Short Bed, 1974-2010 - Ford F150 / 250 / 350 6" 6"" - 6" 8"" Short Bed, 2004-2010 - Nissan Titan 6" 7"" Short Bed, 1993-1998 - Toyota T100 6" 6"" Short Bed, 1999-2010 - Toyota Tundra 6" 6"" Short Bed, 1999-2010 - Chevrolet Silvarado 5" 8"" Short Bed - with Tailgate Down, 1999-2010 - GMC Sierra 5" 8"" Short Bed - with Tailgate Down, Dimensions: 76 x 63, 5 x 12