2 pointsI use peel n seal from Lowes. Same stuff as dynamat- it's just a little thinner and like 20% of the price of dynamat or fatmat. You could always double or triple the layers if you really wanted to. Rubbery/tar like adhesive and aluminum skin. Can't rust, wont come off easily, its a water tight seal, and really works. Watch these vid for info for what I did: https://www.youtube.com/watch?v=c7xi6lAeIog&t=114s Will do inside of door skins when the time comes. Roof is also done.