Perforating the rear deck allows more bass to travel into the cabin from the trunk, where aftermarket subwoofers are traditionally stored. Our Rear Deck Lid Perforation package is great for vehicles that have more trouble getting the bass into the cabin. We typically offer this package for couples and sedans that have thick rear, which make it hard for the bass to travel through. This is also an expensive addition you can easily add to gain more volume from your sub-stage.