JB+ Tuner for Mercedes-Benz 2011-2017 W204 SLK 250, C250 and E250Instantaneous increase in Power and Torque! Take your gasoline powered SLK 250, C250, and E250 to the next level with this simple plug and play tuner. Increases torque and power across the power band with the most noticeable increases coming at lower RPM and throttle positions where you really need them. In addition to adding power and torque it reduces turbo lag and improves throttle response. Gains are up to 20 hp to the wheels and 40 torque to the