DC-DC Converters are used to step up or step down DC Voltages. This model is programmable and so can be used in a variety of ways. It was specially developed for use in motor vehicles with the purpose of regulating the charge from the vehicles alternator to an auxiliary battery. In particular it was designed for use with the type of smart alternators and dynamos used on vehicles such as the Sprinter Van where the output voltage can vary dramatically. To avoid interfering with the vehicles electronics, which might cause warranty issues, the buck boost converter can be programmed to use its built in vibration sensor to only operate when the engine is running. The output produced by the converter can be regulated to suit the requirements of the auxiliary battery system, and in the case of Lithium batteries it can prevent excessive load on the alternator by limiting how much charge is available for the Lithium battery. This sophisticated device is a clever workaround to all kinds of difficult problems that can be encountered when making modifications to these vehicles.