The power of my new box having passed away and the time to get another bush deep in my being long enough I turned to this model that supports entirely the required amperage and virtually without heating. The voltage change is done by turning a knob (5V, 6V, 9V 7.5V and 12V 2250mA - 13.5V and 15V 1800 mA), I only regret that these data do not appear in the datasheet of the product. The output bits are quite numerous and allow a polarity reversal but nothing is planned to store them and I'm not sure to find them all for future use, probably because I am not so meticulous.