QD EXHAUST Ducati Monster S4 Full Exhaust System "Ex-Box" (EU homologated)Full exhaust system by QD Exhaust, complete with collectors, fixed catalyst and removable dB killer. This exhaust system is based on the resonance chamber concept. A lower and closer to the road barycentre allows a stable position during the change of direction. Being located under the front wheel axle, decreases the tail lift generated by the braking inertia. Look and lightness are the Ex Box series advantages, which give to your motorcycle a better