Check the listing for details. PAC AP4-GM61 Amplifier Integration Interface for Select GM vehicles with Bose sy. Condition: New. Listed at 300.00 USD. Today's modern vehicle audio systems are becoming increasingly more sophisticated and complex. PAC engineered AmpPRO to dramatically simplify the installation of upgraded amplifiers in data-bus-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! BenefitsFactory sound system upgrade Time-saving designPrevents the need for summing and audio correction devicesReliable PAC quality Features Upgrade solution for factory, fixed level, data-bus controlled sound systemsThe time-saving design prevents the need for summing and audio correction devices.Variable volume, fade, balance, bass, mid, and treble audio settingsRetains OnStar, Bluetooth, navigation, safety systems, and all warning chimesFront, rear, sub, and center channel preamp outputs (5 volt RMS)Provides full range, flat audio output for a solid audio foundationCustomized OE bass, mid, and treble center frequency selectionPlug-n-play installationRemote sub level controller INCLUDEDOptional TOSLINK optical output INCLUDED Includes AmpPRO moduleHarnessBass knobKnob harnessManual