Product review (4 stars): Using on an old HOMART horizontal kitchen fan.
Works with a fan with motor  I had replaced on an old HOMART (yes) unit that vents straight out the wall. I had to cut a piece of rubber hose to hold the screen tight because I used with the old grill cover. I also added a piece of window screen material to keep mosquitoes out that can fit trough this filter. This might then need to be cleaned more often.