very useful indeed ang 3rd brake light. Bagay ito dun sa mga drivers ni di man lang tsine-check if their tail/stop bulbs are working, some didn't know na dapat when they replace these bulbs dapat sabihin sa suking auto supply na "double" yung ilaw. Sa gabi kasi its hard to distinguish when the vehicle in front of you is stopping because naka-on kasi ang tail lights kaya this 3rd lamp talagang very useful. Nag-DIY nga ako dun sa mga vehicles namin who doesn't have one.