I'd opt for a lighter plug that has a built-in fuse. At the very least you should put an in-line fuse very close to the plug. The wires in the small power connector to the K2 can short and you'll have a melt down if you are not fused at or inside the ligher plug. DigiKey has ligher plugs that have a built-in fuse in the tip plus an LED to let you know that you are getting power to the plug.