All of our headlight kits are 12 volts, if you are not going to use the headlights very often you can connect them directly to the batteries as shown in our instructions that are provided with each kit.
If you will be using the headlights more often, then we do recommend a voltage reducer. The voltage reducer will connect to your entire battery pack and wire into the voltage reducer, the voltage reducer will then reduce the voltage down to 12 volts so you can connect any 12 volt accessories you would like to it, including your headlights. The voltage reducer sizing information can be found here: Voltage Reducer Sizing
All of our headlight kits can be found here: Headlight Kits For Sale