OK...bear with me if you think my question is strange/stupid/etc..

Background: I am in the process of the getting a Vortech SC installed on my car. My car has an Invidia exhaust (along with a variety of other goodies). I have been thinking about putting the OEM exhaust back on the car due to the noise levels. I really like the Invidia but which it was quieter even with the silencers in.

Yesterday...I pulled one of the silencers out and noticed that it has a small amount of "steel wool" material wrapped around it?

What is this steel wool material used for? If I increase the amount of steel material around the silencer will it help in reducing the sound level? Has anyone does similar things before? If so...where can I get the material..etc..etc.

Thanks,
Jeremy