Akrapovic Exhaust Headers BMW R12 / R12 nineT / R12 G/S Features: A combination of beautiful machining and hand welds CNC machined flanges Air-tight quality controlled production means your exhaust will be perfect High-quality, silicon-shielded stainless steel exhaust springs Optimized to maximize lean angle Note: ECU remapping is recommended in order to prevent check engine light and optimized performance and throttle response.