So if you are familiar with how the Power Commander 5 (PCV) works, this switch is a must if you live in an area where you either want to try different maps on the fly or like myself, I keep the original factory OEM map in position 1, and my race only map in position 2. Watching the look on the testers face when I flip the switch and tell them go ahead and run the test and it passes every time for the last 3 years. That alone was worth the switch but the switch can be used to turn the Auto tune on and off if you have that installed. A must if you can afford and plan on getting the PCV, plan on getting this switch. the cable is long enough to have it installed on the handlebars without any issues regardless where you physically locate the PCV unit, where it wires in, with just 2 wires and was very easy to understand installation.