They are absolutely 100% stainless steel, just not a good grade (not 304 which polishes to a chrome like finish). I'm just saying once you scratch the metal, it can be polished out, but the deeper the scratch the more aggressive you have to polish. You probably can't hurt them anymore than the burnt plastic has done, I'd just be careful. Try a little 00 grade steel wool pads. I've polished my Borla and Hooker exhaust with this stuff and never hurt either. The Hooker exhaust tips were chrome not stainless but the 00 grade steel wool pads didn't harm them. The 00 grade may not be aggresive enough to remove the burnt plastic.
