http://www.bmwtradeparts.co.uk/PDF/W...uelFilters.pdf

Claims ~4um at 99.5% filtration. And claims water protection, although there's no way to drain the water out.

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2011 335d Sport Package/Cold Weather Package

2004 Ram Cummins with lots-o-mods
1990 YJ Repowered with modified Cummins B3.3T