PAC Audio Volt-39 is an adjustable voltage adapter that allows you to adjust the voltage output to ensure optimal performance for specific automotive components or devices. The adapter can accept an input voltage from 10 volts to 24 volts and allows you to change the voltage output to 3.3 volts, 5 volts, 6 volts or 9 volts. The output voltages are reliable and unaffected by input voltage fluctuations. Although it accepts voltage up to 24 volts, it is not intended for installation in 24 volt systems.