This is a simple jumper plug that acts as a "dummy" replacement for your cruise control, so that you can remove the main box without having to reverse all the wiring.  You simply unplug the cruise, and plug in this jumper in its place and your car will behave normally (but without cruise).  This is useful, for example: if you wish to send your cruise to us for testing/upgrading/custom programming;  if you have a problem with your car and want to determine if it is the cruise causing the issue before you take it in for repair;  you simply wish to remove it before having your car serviced so your dealer isn't faced with any unknowns (the last two examples are good practices with ANY electronic aftermarket part to best preserve your car's warranty).