Tail light bulb for 2004 BMW X5

7506 appears to be the correct bulb from all the parts look ups I've searched. It is a signal filament simple bulb that twists in. It is not a plug in with multiple terminals. If you are speaking of a brake light or turn signal bulb, then it's different. ut for a "back up light bulb" - the white light that comes on with the reverse gear engaged - then it's 7506.