Measure Width Your trunk interior needs to be slightly larger than 32 inches wide (preferably as close to the trunk rear as possible) in order to comfortably install the frame and your subwoofers | Measure Depth & Height Ensure you have enough clearance both top-to-bottom (13.25 inches) and front-to-back (14 inches) to snugly fit the box with enough room to allow for installation and maintainance | Measure Subwoofer Frames The box has 11-inch diameter cutouts that will fit most 12-inch subwoofers, but consult your subwoofers' manual and measure precisely to ensure a perfect fit |