Originally Posted by Trav
There is magnetic stainless.
Quote
Ferritic Stainless Steels such as grades 409, 430 and 439.
Martensitic Stainless Steel such as grades 410, 420, 440.
Duplex Stainless Steel such as grade 2205.
To add to this, higher end exhaust systems like Borla use T-304 stainless. T-304 is not magnetic. I think most modern OEM exhausts use T-409, which is magnetic (and will get a light surface corrosion over time, turns reddish).
The exhaust tip you show is likely inexpensive chrome plated mild steel. I say that because of the cheap folded seam.
Scott