True but it stinks up your truck I used that stuff in my old ranger.

 

I used Raammat and I love it. Its not as expensive as dynamat, butyl based, and thicker. I put 2 layers in my doors and I also sealed the access holes to the doors. I also put it along the back wall and floor and I plugged up 1 rear vent hole. I would for sure do this again, it didnt make this amazing difference, like I can still very easily hear the drone from my magnaflow exhaust. It did help none the less. I used to listen to my radio at 20, I now listen to it at 14 with the same results so some would claim this is a 6db increase. 3db is when most people can tell a slight difference so take what you can from that.