I have not used them yet . This will be the first time using them.I still have the standard ones. The only thing I look at is the color of the filter when I take it out.
it is great to order several months at a time so I have them when it is time to change them. air is always more clean when filters are changed regularly.
The filters that i received are a good quality as well as i feel that the air is being filtered breedability and the sizes have matched what i require for my home
i bought these before & loved them. this time the 1st out of the 4pack . created so much flow resistance that it made an awfully loud noise and was so much reduced airflow that the filters bent und the pressure
I am very satisfied with these filters and the ease of receiving them autoshipped every month. They arrive sufficiently early before the first of each month.It was necessary for me to find an online supplier due to unavailability locally.