[Billett]

Couldn't tell you for sure. I got some reflectix from lowes, but that's more for heat insulation. They probably sell sound deadener, but it wouldn't be as good for the application as some of the stuff you can get online. I went with FatMat, but there are plenty you can get for cheap that work fine. I got 25sq ft on amazon for $55, but I'd go with 50sq ft.