Product review (4 stars): It does the job.
I realized I had to replace my old vent cover when I dryer decided to stop drying.  The cause- i found a bird's nest inside my vent.  The bird guard I think will prevent any more birds from habitating in my laundry vent.  Not much else to say.  It looks like its doing what its intended to do.  For the price you cant go wrong.

Its plastice and the vents are light enough when hot air blows from the dryer, it should easily lift.

Its seems good so far.  I've had for approx. 1.5 months