The most recent order of 16x20x1 MERV 11 filters appears OK. But on taking out the last of the previous order (same specs) I noticed that the filter was not sealed in the frame, meaning that the last month of operation subjected us and our heating unit to unfiltered air. See the photo. Observing this, I examined every filter I have remaining for similar defects; found none.I wonder how you could specify that you are supplying MERV 11 air filters which have a few square inches of "hole" through the filter? What is your QC program? How often do you test the filters? How can I be assured that the filters you supply meet MERV 11 standards?