This product is a tune change for 2017 - 2023 GMC/Chevrolet HD with 6.6L Duramax engines. It allows you to change from Multi - tune to SOTF, from SOTF to Multi - tune, or from Multi - tune/SOTF to Single tune. Note that these are only tune files. You'll need an HP MPVI3 Device and Credits. Part Number: GDP403UP - DWN.

How to use: First, make sure you have an HP MPVI3 Device and the necessary credits. Then, use the device to load the tune files according to the change you want (Multi - tune to SOTF, etc.). Note: These are just tune files, so the device and credits are a must. Maintenance: Keep your HP MPVI3 Device in a dry and clean place. If you encounter any issues, contact customer service for help.