An EcuTek tuning license is needed on each ECU that is flashed. You only need ONE for the car, once it is flashed the license stays in there. If you are not buying a tune make sure to select that in the options as our pricing varies. You must provide your dongle ID and registration code for us to be able to apply the license. This can be found under help - feature and license information in ProECU. If you don't know it then enter any characters and please email us the information when you have access to it.