KOSO voltage regulator Most KOSO instruments require a 12 volt DC power source for proper operation. Since not all vehicles are equipped with a matching battery or a matching controller, KOSO has developed a current controller. By installing this regulator, it is now possible to use KOSO tools in vehicles without batteries. All you need is a 12-30 volt AC or DC power source, which is therefore at a constant voltage of 12 volts to 15 volts DC. Technical specifications: Input: 12-30 V AC / DC Output: 12-15 volts DC Resistance: 6 Watt Delivery contents: 1 piece