Replaces factory radio in select GM(R) SUVs & trucks while retaining OnStar(R); Plug & play--no cutting or splicing into factory plug; Communicates directly with OnStar(R) ;module to prevent false triggering & eliminating unwanted audio noise; Onboard amp will drive two 4W speakers in stereo ; For use with existing factory speakers or external speakers; For non-Bose(R) vehicles;