I was disappointed not only in the construction of the filter but nowhere is there any mark that it meets a MERV 13 accredidation. I have no idea what this filter is rated.
Poor fit - It is a bit of a misrepresentation as all of the dimensions were noticeable short - at least 1/2" to the nominal. 3M's filter is 4.5" thick compared to 3.5".
I bought these to have on hand to replace filters I had just installed, so it'll be a while before I will use them. They did arrive in a timely manner.