Originally Posted by powers1

Where are you in the uk?Call Bmw GB and they will give you your nearest dealer.
My local dealer in London NW10 is Holland Park.(0208 89607767....parts direct).
Dont know what year is your X5!Assuming you have a <2004 pre-facelift) the parts no.s you need are:-

REAR UNDERBUMPER SPOILER KIT(3PCS)
51.12.7.062.599......left cover
51.12.7.062.600......right cover
51.12.7.062.601......spoiler

FRONT UNDERBUMPER SPOILER(I PC)
51.11.7.062.604....spoiler