Headlight brightness ?
I used H13 bulbs for the headlights (direct replacement) and 9005s for the fogs (they have the tip of the bulb coated to reduce glare).
I used the regular SilverStars:

because the Ultra's had not been released yet:

Either should work. Just be careful that the Ultras just aren't a high wattage, as it could cause your fog lenses to melt. People have had problems with that with the round fog lights, my square ones work just fine.
- NCSU




