Why We Choose HJS Catalytic Converters: 
HJS German imported catalytic converters are made from some of the highest grade materials you can find in a catalytic converter. This yields high performance gains and longevity so it wont deteriorate over time like lower grade catalytic converters. These catalytic converters flow up to 93-95% of a straight pipe in most applications. The benefit is that you get the "straight pipe sound" while still being able to provide enough emissions scrubbing to prevent a check engine light.    
Inject new life into your BMW F87 M2 with a perfect high-flow catted downpipe! Genuine 200-cell HJS catalyst instantly adds power and sport sound without triggering a check engine light!