needs no drilling, cutting or modifications to stock wiring. Key Features: Direct-mount exhaust brake dramatically cuts downhill speed without using wheel brakes. Pays for itself in reduced brake wear and brake maintenance Saves brake wear-and-tear Controls Downhill Speed A total system solution Value-Priced Braking! For use on Automatic Transmission equipped trucks Includes Computerized Brake Controller/SmartLock US Patent #6,152,853 A 50 State Compliant CARB E.O. D-161-140