Heavy duty stainless steel V-Band clamp for turbo discharge or exhaust setup.  The V-Band Clamp are sized based on the flanges that you are using.

Outer Edge measurement refers to the outer diameter ring of the V-Band clamp ring. 

2.00" Outer Edge - 2.48" - 2.80"

2.50" Outer Edge - 2.99" - 3.31"

3.00" Outer Edge - 3.58" - 3.80"

3.50" Outer Edge - 4.00" - 4.33"

4.00" Outer Edge - 4.52" - 4.83"