Please see http://www.realoem.com/bmw/showparts...01&hg=63&fg=05

You need no. 11, 12, 13 for fixing the ballast onto the bracket. Since the ballasts are not oem product, you have to make sure that the size of the ballasts are same with the oem one, otherwise, you may not fix them onto the brackets.

I suggest you buy the oem product, the Hella ballast, it comes with the rubber cap so that you can seal the plastic cover for HID bulb to prevent condensation.

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--2004 E53 X5 4.8is - ECE version; right hand drive; Located in Hong Kong; ext. black sapphire metallic; int. leather black; adaptive dynamic bi-xenon headlights; 16:9 onboard monitor w/o navigation; 20" genuine BMW Y-spoke 214 wheels with Bridgestone Dueler H/P Sport tires; Int. rear view mirror w/ compass.