programs engine for more power. can be programmed for towing, fuel efficiency, or change octane level you run. also has crawl mode for off-roading. can delete TPMS, adjust tire size and gear ratio, adjust automatic shift points, and much more. 

was used on 14 JK should work on all JKs up to 14 and 98 and newer TJs not sure about other models please check with superchips to confirm this works for you model prior to purchase! no returns.