Bests & Worsts Reviews from Amazon

Maybe I'm just being overly picky. I received the 6 filters I ordered in a plain brown box. OK, no problem. But upon inspection of each filter I noticed none of the filters indicated the MERV rating. This is the first time I've ever purchased filters (regardless of brand) where the MERV rating is not clearly indicated on the filter. So, I have no way to verify that what I purchased is what I got. Quite frustrating...