ITEM NAME:Boost Step-up Power Module High-voltage Generator Converter DC3.7v-7.4v LJ Boost Step-up Power Module High-voltage Generator Converter DC3.7v-7.4v LJ a.imagelink a:hover.imagelink {color:#60000;.1x 3v-6v to 400kV Boost Step-up Power Module. If so you can 6V maximum power output. current, small size, high efficiency, simple external circuit ( just plug in the switch, the battery can be ). Input power cable length: about 10mm ( red is positive ).