[m4xm1l10n]

Originally Posted by my06clk

On the Bi zenons the bulb mounts to the ballast and the entire assembly is held in by a turn lock device. it's easy t change..

I paid $125 for my bulb at the dealer ( Ouch!! ). no need to change both of them unless the other is bad. I did mine about 9 or 10 mos ago and you could not tell which one was the old bulb. There was no difference in color.

They sell them online, but there is a slight difference on how the bulbs mount between years on the W220. I think there are 2 or 3 variations. The parts guy showed them to me when I purchased mine.

+1