they dont use an external source, you wire them into your headlight switch, works as normal, has dimmer, everything. I used a bezel, and the cut outs look complete normal and stock. The real issue is it a quality product, it illuminates very well and is easy to read and tasteful. The different between these gauges and the stock ones are the color and some better technology, that is it. Bulbs that go out behind your gauges SUCK, there is nothing good about them.
I'll never understand why someone will prefer those glaring instrument clusters that clash with the rest of the car. The stock setup is easy to read, easy on the eyes, made by FORD, and most importantly, it actually matches the interior lol.
