I own a late W124 with the filters, I replace them every year (2 till date) - the first ones I removed were black as sin and packed flat with dirt/leaves etc. They had MB part no. on them and were manufactured by Micron air.

The ones I put in are also micron air but not OE.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)