You'll have to get in touch with Phil at
MINI PIRATE.com || 2008 || Mini Decals & Graphics for your new roof chequers, he'll do a MUCH better job than BMW will

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My chequered mirror caps faded after a while too

, keep your eye's open in the classifieds or ebay

, if you can't find chequered one's maybe change to black or something like that? Will be much cheaper getting second hand ones, people change them quite frequently so fairly easy to get hold of them

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Good luck
John