Carbon Cabin Air Filter replacement

So Im changing the Cabin Filter on my dads BMW X5. But now instead of buying the filter from the dealership for like $60, we went the cheap route and bought it online for $12. The only minor problem now is, the new filter doesnt have the arrow of which way to install the filter like the dealership filter does....

might be dumb question but my question is, does it really matter which way to install the filter? One side of the filter is the actual filter media and if you flip it over is the carbon... should I install it so the air flow goes through the carbon first... OR do i install it so the air flow goes through the filter media first?

 

Filter media first.

 

thats what i thought. my neighbor thats a mechanic confused me and said it goes thru carbon first?!