Product review (4 stars): A replacement for one which broke
I had one of these, similar, but not the same for many years. It finally died, with the handle snapping off, and one of the plastic clamps biting the dust with it. The handle allows you to choose IN or OUT for the dryer air.
I put an old stocking over the front. I don't trust the rather wide grating filter to grab fine dust. The screws on the metal clamps which I bought with this had to be tightened almost to the end. Seems like this unit is a bit narrower than my old one, but it fits.
BTW, these are great gizmos to add a bit of humidity to a heated basement which can get dry in the winter. When I'm using the dryer with the air directed IN, I can turn off one of the humidifiers.