

2012 Rav4 floor repair : is this sound deadener?
Framed in red on the "before" pic, is this sound deadening membrane like Dynamat?
Rust was developing under some of these, so I scraped off the ones that were coming off easily.
I've finished priming, got my seam sealer ready for tomorrow to reseal the joints I cleaned up and then will move on to reapply new sheets but would like to know what that is exactly.
Thanks a lot guys and gals.