Only fits Shallow mount subwoofers. Mounting Depth: 3-1/2 Inches One of the best options for a regular cab truck is one of our ported enclosure that are specifically built with a truck cab in mind. This enclosure will work a wide range of brands and subwoofers but you do need to look out for the mounting depth which is somewhat shallow. A ported enclosure is tuned to maximize the bass output within a certain frequency response range and since you are limited to the number of subwoofer you can run in a truck it help balance the difference in output. Our boxes are made from precision cuts of MDF. They are then liquid nailed, nailed and completely sealed. We then wrap them with high quality carpet that matches most vehicle interiors. All Boxes feature high grade spring loaded terminal cup(s) for the absolute best connection possible. All the custom series enclosures are made to fit precisely into your vehicle to the get the max performance from every extra inch of wasted space. We guarantee you will not only see a difference in the quality of the boxes we build, but you will hear the difference and that is what is it is truly all about.