actually they are fitted as standard with a runner grommit over the plug cap whicch also forms the seal in to the plastic surround, and as adam says crappy mechanis always leave these off when they fit lb05f plug caps when replaced. these do have their own seal but they arent good enought for the job! even if the rear mudflap wasnt there as long as it had the right seal there it still wouldnt be a problem!
m
March 2010