I have a feral cat colony at my home and from time to time, cats are in my house. That can cause havoc on my HVAC system - cat fur wrapped around my coils - but that is in the past! Now, with my Filtrete filters, almost NO fur makes it upstairs to the coils. And I can change my filters every three months, just like everyone else! Hurray for 3M/Filtrete - now my coils have their extended life!