Radio replacement interface with OnStar(R) retention for select GM(R) Class II vehicles with or without Bose(R) sound system; Rear-seat entertainment activation; Provides plug-in-connection for SWI module (sold separately); No steering wheel button mapping required; In-field updateable firmware via USB using PAC-UP; Retains OnStar(R) when the factory radio is replaced; Retains Bose(R) amplified audio system, if equipped; Provides 10A 12V accessory output; Retains all safety warning chimes; Navigation radio ready; Maintains a “healthy” status on the Class II databus; Retains rear-seat radio controls; Retains rear-seat audio (connects to aftermarket radio aux input); Plug-in installation for vehicles with 24-pin harness; Includes OS-2X module, vehicle wiring harness, chime module with 4-level adjustability & instruction manual;