I been using this one product for awhile for my central hearing and cooling it works great

Very good quality. Only kind we use.

My son and I have bad allergies, we constantly sneeze and cough. I had no clue that the type of filter you use could make a big difference. I notice we don't sneeze and cough as much so to me these are awesome.

What can you say about a furnace filter...does the job.

For years I have been using these filters and they fit snug. Now 3M has reduced the size and now the filter is loose inside intake and each furnace start and stop the filter makes a noise from the suction pulling filter up when on then falls down when off. Disappointed with companies reducing product quality especially 3M. I have to use duct tape to hold filter in place which is 3M also and it used to stick better for years and now I have to use more tape to hold due to this product quality also reduced.