This is a DSP switch to change tunes on a duramax truck. This is required to change tunes on a 2006 and newer duramax, 2001-2005 can be switched serially through an Edge CS/CTS monitor.
Please ensure to select the correct engine model from options.
Returns are accepted within first 30 days and are subject to a 15% restocking fee. Returns are not accepted after 30 days.