Today's modern vehicle audio systems are becoming increasingly more sophisticated and complex. PAC Audio engineered the AmpPRO 4 Interface for select GM 2014-2019 vehicles to dramatically simplify the installation of upgraded amplifiers in databus-controlled amplified sound systems. AmpPRO allows you to keep the original radio's fit, finish, and features while giving you the freedom to improve the audio performance in record time! The module also retains all audio from other vehicle features such as factory Bluetooth and all warning chimes. A sub level controller and optical output are included.