[Johnasara]

The DSP switch allows you to change programming on the fly.You can load up to 5 different programs in your ECM and acess them with the switch

 

[Johnasara]

You hook up two wires to your computer and mount the switch somewhere in the truck. Then you have to either purchase a DSP tune or make your own and do a full reflash of your computer. I made my DSP from the tunes I got From Mike. It is not that hard if you are computer savy and pay attention.